Table of Contents Ignition Management Subject Page Ignition Management .3 Principle of Operation.3 Ignition System Inputs .4 Ignition Coils.4 Spark Plugs.6 Knock Sensors.7 Superknocking.8 Multiple Ignition Pulses .9 Crankshaft Position/RPM Sensor (Hall Effect).10 Crankshaft Sensor (N55) .11 Service Information.13 Ignition Coils.17 Knock Control .18 Spark Plugs.20 Spark Plug Diagnosis (HPI engines).21 Engine Misfire Diagnosis.22 SI B 12 06 10N54- Misfire Faults, Diagnosis with ISTA .25 SI B 12 11 10 N54, N54T, N55 - Diagnosis for HDP High-pressure Faults .33 Initial Print Date: 03/11 Revision Date: Ignition Management Model: All Production: All After completion of this module you will be able to: • Understand how spark is formed and used in BMW engines • Perform an ignition primary scope measurement • Perform an ignition secondary scope measurement • Interpret the spark measurements and relate them to diagnosis • Understand optimized emission • Describe how the ignition system is monitored 2 Ignition Management Ignition Management Example of IPO for an Ignition Management System SIGNAL I- INTAKE AIR TEMP IGNITION COIL CONTROL (6XL One of the main purposes of the ECM is Ignition Management which includes the actu¬ ation of several components. In the following pages you will find a generic explanation on how this system works. For more detailed information please access BMW Training Reference Manuals found on-line. Principle of Operation Ignition Management provides ignition to the combustion chambers with the required voltage at the correct time. Based on the combination of inputs, the ECM calculates and controls the ignition timing and secondary output voltage by regulating the activation and dwell of the primary ignition circuits. The ECM controls and monitors the secondary ignition output including Misfire Detection. The ECM has a very “broad” range of ignition timing. This is possible by using a Direct Ignition System, or sometimes referred to as “Static Ignition System” (RZV). Reliability is also increased by having separate individual ignition circuits. The Ignition Control is determined by the ECM (load dependent). The ECM will calcu¬ late the engine “load” based on a combination of the following inputs: • Battery Voltage; • Accelerator Pedal Position; • Air Flow Volume; • Air Temperature; • Engine Coolant Temperature; • Crankshaft Position / RPM; • Camshaft Positions (Cylinder ID); • Knock Sensors; • *ln a Turbocharged engine, Boost Pressure is also used. 3 Ignition Management The dwell time will be regulated based on battery voltage. When cranking, the voltage is low and the ECM will increase the dwell to compensate for saturation “lag time”. When the engine is running and the battery voltage is higher, the ECM will decrease the dwell due to faster saturation time. The Crankshaft Position/RPM signals the ECM to start ignition in firing order as well as providing information about the engine operation. This input is used in combination with other inputs to determine engine load which advances/retards the ignition tim¬ ing. Without this input, the ECM will not activate the ignition. Cold start is determined by the ECM based on the engine coolant temperature and rpm during start up. A cold engine will crank over slower than a warm engine, the ignition tim¬ ing will range between top dead center to slightly retarded providing optimum starting. When starting a warm engine, the rpm is higher which results in slightly advanced timing. If the engine coolant and intake air temperature is hot, the ignition timing will not be advanced reducing starter motor “load”. Ignition System Inputs The ignition system on the engine management system uses several inputs to control ignition functions. Proper ignition timing control is dependent upon inputs such as RPM, throttle position, crankshaft position, air mass and temperature (coolant and intake air) and in our turbocharged engines, intake boost pressure. Most of the ignition system components have remained the same for all NG6 engines. There are some minor changes to the ignition coils that apply to all versions. The coils have been optimized for more durability. Ignition Coils The high voltage supply required to ignite the mixture in the combustion chambers is determined by the stored energy in the ignition coils. The stored energy contributes to the ignition duration, ignition current and rate of high voltage increase. The Coil circuit including primary and secondary components consists of: The Coil Assembly contains two copper windings insulated from each other. One winding is the primary winding, formed by a few turns of thick wire. The secondary winding is formed by a great many turns of thin wire. 4 Ignition Management The primary winding receives battery voltage from the Ignition Coil Relay (in the IVM) which is activated by the CAS Module. The ECM pro¬ vides a ground path for the primary coil (Coil Terminal 1) by activating a Final Stage transis¬ tor. The length of time that current flows through the primary winding is the “dwell” which allows the coil to “saturate” or build up a magnetic field. After this storage process, the ECM will interrupt the primary circuit at the point of ignition by deactivating the Final Stage transistor. The magnetic field built up within the primary winding collapses and induces the ignition voltage in the secondary winding. The high voltage generated in the secondary winding is discharged through Coil Terminal 4 to the spark plug (insulated by the boot connector). Index Explanation 1 Coil Assembly 2 Insulator Boot 3 Spark Plug 4 ECM Final Stage Transistor 5 Secondary Coil Ground The primary and secondary windings are un-cou- pled, therefore, the secondary winding requires a ground supply (Coil Terminal 4a). The high voltage generated in the secondary wind¬ ing is discharged through Coil Terminal 4 to the spark plug (insulated by the boot connector). The primary and secondary windings are un-cou- pled, therefore, the secondary winding requires a ground supply (Coil Terminal 4a). Secondary Winding Insulator Boot } The ECM uses “pencil type” ignition coils. The individual ignition coils are integrated with the insulated connector (boot). The coils are removed by lifting the swivel latch connector retainer to release the wiring harness, apply a slight twist and lift the assembly upwards. The primary ignition cables are routed on the top of the cylinder head covers. 5 Ignition Management Spark Plugs The spark plugs introduce the ignition energy into the combustion chamber. The high voltage “arcs” across the air gap in the spark plug from the positive electrode to the negative electrodes. This creates a spark which ignites the combustible air/fuel mixture. The spark plugs are located in the center of the combustion area (on the top of the cylinder heads) which is the most suitable point for igniting the compressed air/fuel mixture. The spark plugs used on BMW Engines are designed by NGK. The plugs use an Iridium center electrode. The center electrode is only 0.6 mm thick. The insulator is also redesigned. The new spark plug technology allows for longer service life and improved cold starting. The correct spark plug for each engine should be used. The Ignition System is monitored by the ECM via the Crankshaft Position/RPM Sensor. If a Misfire fault is present, the ECM will deactivate the corresponding fuel injec¬ tor for that cylinder. Engine operation will still be possible. The spark plugs for the N51 and N52KP remain the same as N52. However, the N54 uses a completely new spark plug from Bosch. The spark plug design consists of a 12mm thread which contrasts from the 14mm design on the N52 which prevents any possibility of improper installation. The hex on the spark plug is also a 12 point design which requires a special tool. The tool (socket) has a “thinwall” design to facilitate access in the confined area of the N54 cylinder head. Iridium is a precious metal that is 6 times harder and 8 times stronger than platinum, it has a 1,200° F higher melting point than platinum and con¬ ducts electricity better. 6 Ignition Management Knock Sensors The knock sensor registers structure-borne vibrations (knocking). Knocking combustion can damage the engine. The data from the knock sensor make it possible for the DME to implement countermeasures. Abnormal, reverberating combustion processes can occur under certain conditions in petrol engines. These abnormal combustion processes curtail the earliest possible igni¬ tion timing point and therefore limit the power output and efficiency of the engine. Such combustion processes are referred to as knocking and occur as the result of self ignition of the fuel-air mixture not yet reached by the flame front. Normal combustion and compression produced by the piston cause pressure and temperature to rise, resulting in self-ignition of the fuel-air mixture not yet ignited. This produces flame velocities in excess of 2000 m/s while the flame speed during normal combustion is approx. 30 m/s. Conditions favoring knocking operation include: • Increased compression ratio (e.g. deposits) • High cylinder charge • Poor fuel quality (RON/MON) • High intake air and engine temperature The knock sensors operate on the piezo electric principle. Vibrations from combustion events are converted into electrical signals which are monitored by the ECM. Excessive vibration indicates engine knock which will cause the ECM to retard the ignition timing to retard as necessary. The number of Knock sensors will vary depending on the engine; typically 6 cylinder engines use two (2), V8’s four (4) and V12’s six (6). Note: Excessive knocking will cause the MIL to illuminate. When installing knock sensors, be sure to torque to specification. Under or over-tightening the knock sensors can result is erroneous knock sensor faults or poor engine performance. If a fault is detected with the sensor(s), the ECM deactivates Knock Control and it will set the ignition timing to a conservative basic set¬ ting based on intake air temperature/pressure and a fault will be stored. 7 Ignition Management Superknocking The term superknocking refers to irregular combustion that occurs in turbocharged/supercharged engines. During this process, the maximum combustion pressure increases from approx. 100 bar up to about 200 bar. This situation could be caused by foreign bodies in the combustion chamber such as oil, residual gas or carbon particles that trigger ignition of the fuel-air mixture before the actual firing point. Superknocking cannot be eliminated by corresponding interventions in the ignition sys¬ tem so to prevent engine damage, the ECM reduces the power output when it detects superknocking. Temporary superknocking is caused by individual dirt particles. Fuel injection into the affected cylinder is shut down in the short term (3 to 6 cycles) in response to superknocking. A corresponding fault code is stored in the fault code memory. 8 Ignition Management Multiple Ignition Pulses Multiple Ignition Pulses ensure good spark quality during engine start up. The ECM will activate the ignition coils 9 times (voltage dependent) per 720° of crankshaft revolution. The ignition timing will be progressively advanced assisting the engine in coming up to speed. As the engine speed approaches idle rpm, the timing remains slightly advanced to boost torque. When the engine is at idle speed, minimum tim¬ ing advance is required. This will allow faster engine and catalyst warm up. The multiple pulsing switches to single pulse when: • Engine Speed >1350 RPM (varied with engine temperature) The timing will be advanced when the ECM observes low engine rpm and increasing throttle/air volume inputs (acceleration torque). As the throttle is opened, the ECM advances the timing based on engine acceleration and at what rate. The ECM will fully advance timing for the “full throttle” position indicating maximum acceleration (torque). ECM Relay hdnrn^n^n™ |>- JS: 1 l£l HI - |71 ES| vn •rjm Cmllr dll i IJH * 1 ii^hl 4 0 0 £ Multiple ignition : pulses from each coil ii E PI IM FriF -i r V'A II" 'iff' flw Otfm i "TF1 E T-EU* fatal UrJh nil', j AG | DC | |fpU» ad | PD **&.' P«i1p LiiMUi'UMj LhfliTwiltXJ ihmn 9 Ignition Management Crankshaft Position/RPM Sensor (Hall Effect) The crankshaft position sensor provides the ECM with a 5 volt square wave signal. The ECM calculates engine speed (RPM) and crankshaft position for ignition and injection system operation. The sensor is supplied with 12 volts from the engine electronics fuses and ground from the ECM. An effective signal that can be evaluated is output as from a speed of approx. 20 rpm. The control unit detects the tooth gap in that the measured spacing of the gaps is more than double as great as the previous or subsequent gaps. The tooth gap itself is assigned to a defined crankshaft position of cylinder number 1. The DME synchronizes the crankshaft position with respect to this timing point. With each subsequent low signal it increments the crankshaft position by 6°. Exact assignment is necessary for the DME to be able to adapt the ignition and fuel injection to specific requirements. The time interval measured between two level changes (e.g. High to Low) is therefore divided into smaller units of time. Index Explanation Electrons Hall Module Lines of magnetic force Permanent magnet Power supply Hall voltage The crankshaft position sensor is also monitored for variations in crankshaft speed to determine misfires. 10 Ignition Management Crankshaft Sensor (N55) The function of the new crankshaft sensor is identical to that of the crankshaft sensors used for the automatic engine start-stop function (MSA). The engine reversal detection is required for the MSA function. (MSA is not currently offered in the US.) Index Explanation 1 Connector 2 Dust seal 3 Sensor 11 Ignition Management 12 Ignition Management Service Information A fault survey should first be performed using the IMIB to determine if there is a fault in the primary ignition or secondary ignition. If there is a fault in the primary ignition, testing should include: • Power Supply at the coil (KL 15). • Resistance of the harness and ignition coil primary winding using the Universal Adapter with the ECM disconnected. If there is a fault in the secondary ignition, testing should include: • Primary Ignition. • Evaluation of Secondary Oscilloscope Patterns. The Following are Examples of Secondary Oscilloscope Patterns (consult Repair Instructions for ignition pattern variations per coil manufacturer): This is a normal pattern for one ignition circuit with the engine at idle speed. • Normal Combustion Period. • Normal Ignition Voltage Peak. 13 Ignition Management Multiple Ignition Pulses ensure good spark quality during engine start up. The ECM will activate the ignition coils 9 times per 720° of crankshaft revolution. This is a normal pattern for one ignition circuit when: 1. Normal Combustion Period 2. Normal Ignition Voltage Peak J, | Tld**:* l«.#TLliU ■ ?! t ■ Long Spark Period (1) with Low Ignition Volt¬ age Peak (2). If Spark Period is Fluctuating: • Indicates Low Compression • Contamination on Spark Plug or Defective Spark Plug If instead you measured a Short Spark Period (1) with High Ignition Voltage Peak (2): • Defective Ignition Connector or Resistive Adaptive Boot 1 1111 1 1111 p m | 1111 1 1111 1 h h 1 1 u i | m 1 1 1111 1 n n | TOO SO BO 70 60 40 30 ZO 10 0 Evaluation of Ignition Voltage Peaks at Idle Speed (Multiple Cylinders Displayed). 1. Normal Attenuation (Voltage Reduction) Process 2. Shorten Attenuation Process (arrow)- Defective Ignition Coil 3. Absence of Attenuation (arrow )-Defective Ignition Coil 14 Ignition Management No Sparking Voltage Line (Single Cylinder Displayed) • Defective Ignition Coil. Evaluation of Ignition Voltage Peaks under Sudden Loads (Multiple Cylinders Displayed). • Defective Ignition Coil. Decaying Process is considerably Higher than Ignition Voltage Peak (2): • Lean Mixture. • Defective Fuel Injector. • Low Compression. Allow at least 3 minutes to elapse after the key was set to the “OFF” position before disconnecting the ECM. This will allow sufficient time to complete the DM-TL test. Voltage may be present (up to 3 min¬ utes) causing damage to the ECM if it is disconnected during this time period (arcing). The Repair Instructions should be consulted for additional Oscilloscope Patterns under various engine speeds. 15 Ignition Management When Testing the Secondary Ignition System, use Special Tool (Secondary Voltage Test Cable) #90 88 6 127 050 / SWZ 12 7 050 This pro¬ vides a clamping surface for the IMIB primary and secondary ignition adapter clamps. CAUTION!!! Observe safety precau¬ tions, high voltage is present with the engine running! W127CSQ The ignition current circuit is monitored based on the current in the primary coil. When switching on, the current must be within certain values during defined time thresholds. The following items are monitored: • Primary current circuit of ignition coil. • Ignition wiring harness. • Secondary current circuit of ignition coil with spark plug. • Spark duration. The following defects are detected by the ignition circuit monitoring: • Short-circuit on primary side of ignition coil. • Spark plug. • Line break in ignition wiring harness. • Defective ignition output stages. The following are not detected: • Sporadic faults such as loose contacts in the ignition wiring harness. • Sparkover in the high voltage circuit parallel to the spark gap without producing an interturn fault. 16 Ignition Management In Summary, If the Secondary Ignition Voltage is Too High (Excessive Resistance for Ignition): • Spark Plug Gap is to Large (Worn or Burned). • Incorrect Heat Range Spark Plug. • Compression is too High (Carbon, etc.). • Interruption in the Secondary Ignition Connector or Resistive Adapter Boot. If the Secondary Ignition Voltage is Too Low (Low Resistance for Ignition): • Spark Plug Gap is Too Small (Mishandled on Installation). • Incorrect Heat Range Spark Plug. • Compression is Too Low. • Voltage Leak in the Secondary Ignition Connector or Resistive Boot to Ground. Ignition Coils The ignition coils of BMW enignes have been redesigned for better rigidity and durability. Particular care must be taken when working on the fuel system to ensure that the igni¬ tion coils are not wet with fuel. The resistance of the silicone material is greatly reduced by contact with fuel. This could compromise the coils insulation and result in arcking at the top of the spark plug causing a misfire. • The ignition coils must be removed before working on the fuel system. • When installing new solenoid valve fuel injectors utmost cleanliness must be observed. • After removing the ignition coils use a rag to prevent fuel from entering the spark plug well. • Ignition coils that have been saturated with fuel must be replaced. 17 Ignition Management Knock Control Knock Control allows the ECM to further advance the ignition timing under load for increased torque. Knock Control is only in affect when the engine temperature is greater than 35°C and there is a load on the engine. This will disregard false signals while idling or from a cold engine. Based on the firing order, the ECM moni¬ tors the Knock Sensors after each ignition for a normal (low) signal. KNOCK SEnSORS MONSTER COMBUSTION NO ■&£ 3JUILKR TO A MIGR.DP'JIOME _l— l—LJ JlL \ IT 1 A rl n (\ jl I' l i v H k rx r J\ i* A f jy Acceptable Range Not Acceptable ■—. •. ': If the signal value exceeds the threshold, the ECM identifies the “knock” and retards the ignition timing (3°) for that cylinder the next time it is fired. This process is repeated in 3° increments until the knock ceases. The ignition timing will be advanced again in increments to just below the knock limit and maintain the timing at that point. If a fault is detected with the Knock Sensor(s) or circuits, the ECM deactivates Knock Control. The ignition timing will be set to a conservative basic setting (to reduce the risk of detonation) and a fault will be stored. The “Malfunction Indicator Light” will be illumi¬ nated when the OBDII criteria is achieved. The Knock Sensors should be tested using the IMIB for: • Fault Codes • Status Display - Knock Control (active / not active) • Oscilloscope Display (Low AC Voltage -mV setting) When installing Knock Sensors: • Do not mix the locations! or Engine Damage will result! The Knock Sensors use a combined connection to the engine harness. The Knock Sensor with the shorter cable is for cylinders 4-6. • Do not over tighten attaching bolt! - Piezo ceramic will be cracked. Torque to 20 nm. • Do not under tighten attaching bolt! A lose sensor can vibrate producing a similar signal to a knock. 18 Ignition Management Conditions favoring knocking operation include: • Elevated compression ratio. • High cylinder charge. • Poor fuel quality (RON/MON). • High intake air and engine temperature. Self-diagnosis of the knock control system comprises the following checks: • Check for signal error, e.g. line break or plug connection defective. • Self-test of evaluator circuit. • Check of noise level registered by the knock sensor for the engine. Knock control is switched off if an error is determined in one of these checks. In this case, an emergency program controls the ignition timing. At the same time, a corre¬ sponding fault code is entered in the fault code memory. The emergency program ensures safe, damage-free operation. The emergency program depends on the load, engine speed and engine temperature. 19 Ignition Management Spark Plugs The Spark Plugs should be inspected for the proper type, gap and replaced at the specified intervals. Refer to the Service Information Bulletins: • SI B 12 01 05 High Performance Iridium Spark Plug/Spark Plug Application Chart • SI B 12 01 99 High Performance Platinum Spark Plug/Spark Plug Application Chart for the proper type and a visual of the spark plug (showing effects of combus¬ tion, fouling, etc.) The Spark Plugs should be properly installed and torqued using the following Special Tools: • SWZ 12 1 200 Torque Limiter • SWZ 12 1 171 Spark Plug Socket Never use Air Tools for removal or installation. 20 Ignition Management Spark Plug Diagnosis (HPI engines) Due to the proximity of the spark plug to the fuel injector nozzle, any divergence in the fuel spray may cause possible spark plug damage. This makes spark plug diagnosis an important part of HPI engine service concerns. Information gained by the spark plug diagnosis may indicate possible fuel injector faults. Spark plug replacement interval has been reduced to 45,000 miles on this engines. The illustrations below can be used to assist in spark plug diagnosis: The spark plug above shows a normal wear pattern with no excessive electrode wear or insulator damage. The spark plug above shows a normal wear pattern for a spark plug with high mileage. Spark plug is due for replacement. The spark plug above shows erosion of the electrode on one side which could be an indication of fuel spray “diversion”. The spark plug above shows erosion of the electrode on one side and damage on the insulator nose. This could also be an indication of fuel spray “diversion”. 21 Ignition Management Engine Misfire Diagnosis Engine Misfire is the result of inefficient combustion in one or more cylinders. The caus¬ es of Engine Misfire are extensive but can be grouped into the following sub-systems. Consider the charts below as an additional diagnostic aid once ISTA is connected, the correct fault symptom has been chosen and the fault memory has been interrogated. Follow the Test Module as displayed by ISTA. IGNITION SYSTEM COMPONENT POSSIBLE CONDITION TEST CORRECTION Spark Plug: • Incorrect spark plug installed • Electrode gap closed or too small • Electrode(s) missing • Oil or fuel fouled spark plug • Ceramic insulation cracked Secondary • Verify correct spark plug Ignition • Replace if necessary • Swap with another cylinder Secondary • Wet or moist due to water infiltration, circuit: (wiring,* High resistance due to corrosion. M73-cap, rotor) • Check water ingress, repair, replace • Check resistance value, replace Ignition Coil(s): • Secondary/Primary Circuits open or shorted. Secondary • Housing cracked, damaged. and Primary • Inspect and replace if necessary • Swap with another cylinder Ignition Coil & Engine Harness Connectors • Power supply, Primary control and Primary • Look for open, loose connector, ground (shunt signal) circuits impaired. Ignition & corrosion, crossed or backed out Term 4A feed- pins (also consider ignition unloader or back Preset ECM relay on MY97 and newer cars). Measurements • Determine defective condition, repair or replace. • A secondary ignition oscilloscope display provides vital information about the ignition system’s condition. • Follow the precautions in REP 12 00 Instructions for working on the ignition system. • Use the following scope patterns as a guideline for ignition system diagnosis. J*V* ■.-! »*.n s in 2* m m-w m nn T.TB1 Jk>y-|\Lh , JL l J IIU l-’i hMHrtvr.n-TiUi. l£ ¥/ ... Vwf&rm isriEJ1-F1 C-tSV v *-.->• sW H !fir -9*i tHIHIffl aTiH Frirr Cril 1-1 M^| KrHUflftU'f II £ -JIM - r-h-ll t -rJ; -Ji »4tu * d uAm id I n ■ rij-irWi tanh -nj i MMtmmad uv-iL S-.LJP.J. t£i ki iiukr uM uiHp iryMhrv hr.n iiiil. iiTBrrra stH iiama uirrf n -irni/ wrmwr l> rvrum..n -rr^ “+■?■■ qi b^pii UTy. mn i u ■- L^xi..^i Evaluation of secondary signal amplitude at idle speed. rl m UMwi'u r?i*i km I rwMirvA k nm m m Vii «i> W< « pKT'IrllW. ivl^iK^WlirUi b-MCK i CHl 1. Normal Ignition Voltage Peak: 2. Low Ignition Voltage Peak: 3. High Ignition voltage peak: Spark Plug is OK Gap too small (defective) Gap too large (defective) |o © © ■A* Ji hr t. 22 Ignition Management ONG COMBUSTION - PERIOD (SMALL GAP) win „j rf la. HORT COMBUSTION PERIOD (LARGE GAP) 4... . . r ENGINE MECHANICAL SYSTEMS COMPONENT POSSIBLE CONDITION TEST CORRECTION Pistons, • Hole in piston crown, ring(s) broken, • Idle Quality - Rough Run- • Correct condition as Rings, valve(s) not seating, valve(s) bent, ning Preset. required. Valves, valve spring(s) broken, camshaft lobe • Cylinder compression & Camshaft: cracked, etc. leakdown tests. Hydraulic • HVA oil bore restricted or blocked. • Idle Quality - Rough Run- • Always consider Valve • Engine oil pressure builds up too slow. ning Preset. mechanical com- Actuator * Intermittent Misfire Fault - Not • Listen to HVA ponents when (HVA): Currently Present. • Check Oil Pressure diagnosing misfire. • HVA binding/sticking in bore. • Cylinder leakdown • Inspect for scoring. Vacuum • Unmetered vacuum leaks causing a • Idle Quality - Rough Run- • Correct condition as Leaks: “lean” operating condition. Possible “Excessive Mixture Deviation” ning Preset. Test for vacuum leaks per Repair Instr. and SI B required. fault codes. on “Crankcase Ventilation”. • Interpret Add. & Multiple adaptation values FUEL QUALITY, DELIVERY, INJECTION & EVAPORATIVE SYSTEMS COMPONENT POSSIBLE CONDITION TEST CORRECTION Fuel (quality): • Contaminated fuel. • Clean fuel system, replace fuel. (water, other non combustible). Fuel Delivery: • Fuel pump deliver/ pressure low, restriction in fuel line to fuel rail or running loss valve. • Fuel filter restricted (clogged). • Low fuel in tank. • Check fuel pressure & volume. • Check fuel pump power and ground • Determine restriction/flow reduction, replace component as necessary. • Interpret Additive and Multiplicative adaptation values. Running Loss • Valve stuck in “small circuit” position. Valve: • Check valve • Display “diagnosis requests” in DISplus and test valve for proper function, repl¬ ace valve as necessary. Fuel Injectors: • Leaking fuel injector pintle seats cause rich engine starts with hot ambient temperatures. • Blocked (dirty) injector(s). • Ti Preset & • Check injectors for leakage, status page. • Swap suspect injector with another • Sec Ign scope cylinder, pattern. • Inspect injector, replace if necessary. Fuel Pressure • Regulator defective, causes fluctuation Regulator: in the injected quantity of fuel causing mixture adaptation faults. • Fuel pressure • Check nominal fuel pressure value with engine operating under varied speeds. Evaporative • Defective evaporative system vent System: causing fuel tank collapse and fuel. starvation. • DISplus status, Evap test with press¬ ure tool, purge valve func. test. • Check the fuel tank condition and vent line. • Check Fresh Air Valve on TLEV E36 vehicles or LDP/DM TL and filter on ORVR vehicles for proper system “breathing”. 23 Ignition Management IMPLAUSIBLE ECM CONTROL FUNCTION OR SENSOR INPUT SIGNALS COMPONENT POSSIBLE CONDITION TEST CORRECTION Crankshaft Position Sensor or Increment Wheel: • Implausible signal for misfire detection. • ISTA preset • Increment wheel loose or damaged measurement, (internal on M44, M52 and M54, external on M62 & M73). • Air gap between sensor and wheel. • Noticeable at higher rpm. • Determine defective sensor or increment wheel and replace. Catalyst • Excessive exhaust back pressure Damaged: (bank specific fault present, more noticeable under heavy load and high rpm). • ISTA preset • Determine catalyst condition, replace measurement or repair as necessary. of oxygen sensor. • Back pressure test per SI B with Special Tool. Oxygen • Excessive mixture deviation, Sensor: possible vacuum leaks. • Monitor oxygen sensor signal via DIS preset. • Swap sensor from other bank (if app¬ licable) and see if fault transfers to other bank. Engine • Internal control module fault. Control Module • Misfire Reprogramming. • Check fault • Highly unlikely but must be considered, memory. • Refer to SI B • Check Model/Prod range - reprogram When diagnosing a Misfire fault code, Remember: “Misfire” is caused by a defect in the internal combustion engine or a defect in the control of the engine operation. “Misfire” is the result of improper combustion (variation between cylinders) as measured at the crankshaft due to: - Engine mechanical defects; breakage, wear, leakage or improper tolerances. - Excessive mixture deviation; air (vacuum leaks), fuel and all the components that deliver air/fuel into the combustion chambers. - Faulty ignition; primary, secondary including spark plugs. - Faulty exhaust flow; affecting back pressure. - Tolerance parameters; ECM programming. A Misfire fault code(s) is the “symptom” of a faulty input for proper combustion. When diagnosing a misfire, review the charts to assist you in finding the faulty input. 24 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA CD CO CL 25 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA DFT - Leaking Injector Page 2 r Check Symptom Is this really the symptom described? Let engine cool down below 40°C / 100°F Disconnect low pressure side from high pressure side Check EKP function: * p_fuel(LP) > 4.75bar while EKP is running; if not: follow B1214_DI_KDR * residual pres, of >3.75bar lOmin after EKP was deactivated Check okay t □ Check not okay Follow recommendations of test plan" Connect low pres, side and high pres. side * Activate EKP * Check residual pressure in HP system: read HP fuel sensor value; >3.75bar lOmin after EKP deactivated? If yes: injectors have no leakage. Swap ignition coil and spark plug of misfiring cyl. with OK cylinders; ^Submit TC case for injector replacement. > If only one misfire occurs per bank -> Replace just one injector > If more than one misfire occurs in the same bank -> Replace all 3 injectors of that bank; > If three or more cylinders misfire -^Replace all 6 injectors ^Submit TC case for injector replacement. Determine the cylinder affected by misfire (see misfire fault code) and Environmental conditions Note: * If only one cylinder with misfire occurs per bank -> Replace just one injector * If more than one Cylinder with misfire occurs in the same bank Check misfire frequencys (Environmental Conditions) -> Replace the injector with the highest frequency of misfires per bank Replace ignition coil and spark plug accordingly When replacing injectors, make sure that: * Injector calibration is done (follow SIB 12 26 08) * Clear all DME adaptations T In case of this leaking injector symptom, make sure that: * Check DME 1-Level go to No. 4 * Note: It needs elevated temperatures and high engine loads to evaporate/burn fuel in exhaust system - 1 - Injector Part Number Exit Create and submit TC-Case, where applicable Recheck fault memory after test drive; If clear, return car to customer 26 Ignition Management SI B 12 06 10 N54 - Misfire Faults - Diagnosis with ISTA Check fault memory DFT- Fuel System N54 MSD80/81 E8x, E9x, E6x, E71 Page 3 EKP Module Information: CCC message „fuel pump defective 1 ' or engine does not run at all EKP function check according to ISTA EKP test modules; ‘submit TC case for EKP replacement if necessary DC EKPM Yes Add fuel, delete fault memory For Your Information Definition of the Jong crank 11 complaint: the engine is cranking up to about 3-4 seconds, before it starts quickly LP = Low Pressure System HP = High Pressure System Where to find the HDP’s Production and Serial Number Yes Yes Replace LP sensor, DC LPS DME Low Pressure (LP) System Check LP sensor (except E89): Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 6.7 bar, the LP sensor is faulty and must be replaced; ‘submit TC case for LP sensor replacement if necessary; Check low pressure sensor line: if mounting bracket is welded onto pipe, replace with part number 7 545 725 riu' ,-^ DC LPS DME High Pressure (HP) System HARNESS Yes Update 1-Level With ISTA/P 37.2 or newer If 1-Level < Exxx-10-03-504 Ignore fault entry, delete fault memory SI B12 11 10 No 0x2FBF ^fuel high pressure on release oC injection, pressure too low AND customer complaint is “long cranky No Check LP sensor (except E89): Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 6.7 bar, the LP sensor is faulty and must be replaced; ‘submit TC case for LP sensor replacement if necessary; Check low pressure sensor line: if mounting bracket is welded onto pipe, replace with part number 7 545 725 always . I EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary always DC LPS No trouble found "only Jong crank" complaint"" without fault entry, possibly with info entry 0x2FCA, 0x2FDA, OxFDB ‘Submit TC case for HDP replacement -Yes- Update 1-Level With ISTA/P 37 or newer If 1-Level < Exxx-10-03-502 Check battery voltage; check starter; check crank shaft and camshaft sensors; repair if needed No Check LP sensor (except E89): Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 6.7 bar, the LP sensor is faulty and must be replaced; ‘submit TC case for LP sensor replacement if necessary; Check low pressure sensor line: if mounting bracket is welded onto pipe, replace with part number 7 545 725 DC LPS always EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary always DC OTHER LC No DC EKP ‘Submit TC case for HDP replacement Update 1-Level With ISTA/P 37.2 or newer DC HDP 2FBF -Repair was needed at battery, starter, crankshaft or camshaft sensors- Yes- Check HP sensor; make sure car was sitting more then 15min; follow diagnostic request to compare LP to HP sensor values; the values must not differ more the +/-3 bar; replace HP sensor if necessary Important note: in case the HP sensor value is higher then 9bar, release the pressure by slightly loosening the connection between the injector and the rail and repeat the above check again; in case of repeated failure ‘submit TC case for HP sensor replacement DC HPS 29F1 Create and Submit TC-Case where applicable. Readapt DME and perform test drive on page 1. Recheck fault memory after test drive, if clear, return car to customer OK ‘Submit TC case for HDP replacement Update 1-Level With ISTA/P 37.2 or newer If 1-Level < Exxx-10-03-504 27 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA Check fault memory DFT - Fuel System N54 MSD87 F01, F02 Page 4 EKP Module Information: CCC message „fuel pump defective" or engine does not run at all EKP function check according to ISTA EKP test modules; ‘submit TC case for EKP replacement if necessary DC EKPM Yes Add fuel, delete fault memory For Your Information Definition of the Jong crank" complaint: the engine is cranking up to about 3-4 seconds, before it starts quickly LP = Low Pressure System HP = High Pressure System Where to find the HDP’s Production and Serial Number Low Pressure Sensor, electric Yes Yes Replace LP sensor, DC LPS DME Low Pressure (LP) System DME High Pressure (HP) System Yes- Check LP sensor. Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 6.7 bar, the LP sensor is faulty and must be replaced. DC LPS OKf EKP function check; follow ISTA test module; submit TC case for EKP replacement if necessary DC EKP Check for open electrical circuit between rail sensor and DME; ‘submit TC case for rail sensor replacement if necessary; Note: default value appears as 265bar, when sensor deffective / open circuit DC HPS 29E2 -No- Check for open electrical circuit between HDP and DME; replace components if necessary T ‘Submit TC case for HDP replacement Ignore fault entry, delete fault memory SI B12 11 10 DC HDP HARNESS DC HDP VCV Update 1-Level With ISTA/P 37.2 or newer If 1-Level < Fxxx-10-03-502 1 Check LP sensor. Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 6.7 bar, the LP sensor is faulty and must be replaced. DC LPS OK EKP function check; follow ISTA test module; submit TC case for EKP replacement if necessary ‘Submit TC case for HDP replacement DC EKP Update 1-Level With ISTA/P 37.2 or newer If 1-Level < Fxxx-10-03-502 No trouble found Check LP sensor. Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 6.7 bar, the LP sensor is faulty and must be replaced; DC LPS Check battery voltage; check starter; check crank shaft and camshaft sensors; repair if needed EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary DC EKP DC OTHER LC No ‘Submit TC case for HDP replacement Update 1-Level With ISTA/P 37.2 or newer DC HDP 2FBF -Repair was needed at battery, starter, crankshaft or camshaft sensors- Check HP sensor; make sure car was sitting more then 15min; follow diagnostic request to compare LP to HP sensor values; the values must not differ more the +/-3 bar; replace HP sensor if necessary Important note: in case the HP sensor value is higher then 9bar, release the pressure by slightly loosening the connection between the injector and the rail and repeat the above check again; in case of repeated failure ‘submit TC case for HP sensor replacement DC HPS 29F1 Create and Submit TC-Case where applicable. Readapt DME and perform test drive on page 1. Recheck fault memory after test drive, if clear, return car to customer OK ‘Submit TC case for HDP replacement Update 1-Level With ISTA/P 37.2 or newer If 1-Level < Fxxx-10-03-502 28 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA DFT - Mixture Adaptation Fault Page 5 r Check Symptom Is this really the symptom described? T -Too Rich— Check for possible rich conditions * Visually check monoliths (borescope if available), whether they are mechanically deteriorated; check fault memory for 29F4, 29F5 „catalyst conversion" * Continue following DFT - Leaking Injector on Page 2 DC M | X R | CH Check environmental conditions of fault code: Is it too Rich or too Lean? —Too Lean- Check exhaust side on that bank * Smoke the exhaust system; search for cracks/leakages and replace part if needed * Are 02 sensors torqued correctly; *Submit TC case for replacement, if needed DC MIX EXH * * * Readaptation of the DME Test Drive is needed! Car must be at operating temperature / warm Drive vehicle 50-60mph with 2000-2500rpm for at least 3min (use manual shift, if needed) Perform at least 2-3 drive cycles if possible Let vehicle idle for about 5min Recheck mixture adaptation values (short test GT1) i Check Fuel Quality * Check alcohol content following SIB 13 04 06; In case >15% -> check fuel lines and connections for corrosion * Refuel the car with known good gas * Clear DME adaptations (doublecheck with short test GT1) D q M | X fuel -No- Yes Check Fuel Supply * Check crankcase ventilation pressure * Check fault memory (history) for any indications of lean conditions, 29F2, 29DC, 29F1, etc. * Inspect the fuel tank for contamination like sand, grit, cloudy fuel, etc.; if yes drain the fuel system and *Submit TC case for replacement, if needed DC MIX SUP Problem not fixed Exit Create and submit TC-Case, where applicable Recheck fault memory after test drive; If clear, return car to customer 29 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA 30 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA DFT - Rough Running @ Cold Start Page 7 \ Check Symptom Continue with page 6, following DFT - rough running @ warm engine Check environmental conditions of misfire faults: Is there a misfire fault with engine temperature >50°C? In case of rough running @ cold make sure to: * Check spark plugs; are they wet or excessively sooted? * Check injector calibration values; follow SIB 12 26 08 * Update DME to latest 1-Level Readaptation of the DME -> Test Drive is needed! Car must be at operating temperature / warm Drive vehicle 50-60mph with 2000-2500rpm for about 3min (use manual shift, if needed) Perform at least 2-3 drive cycles if possible Let vehicle idle for about 5min Let car sit over night and start the car cold!! Yes Exit Create and submit TC-Case, where applicable Recheck Fault Memory after cold start; If clear, return car to customer 31 Ignition Management SI B 12 06 10 N54 - Misfire Faults, Diagnosis with ISTA 32 Ignition Management SI B 12 11 10 N54, N54T, N55 - Diagnosis for HDP High-pressure Faults ^ " Page 1 DFT - Fuel System N55 E8x, E9x, E7x EKP Module Rail Pressure Sensor DME High Pressure (HP) System Information: CCC message „fuel pump defective" or engine does not run at all EKP function check according to ISTA EKP test modules; *submit TC case for EKP replacement if necessary DC EKPM Yes Add fuel, delete fault memory N55 E8x, E9x, E7x has no low pressure sensor For Your Information Definition of the Jong crank" complaint: the engine is cranking up to about 3-4 seconds, before it starts quickly LP = Low Pressure System HP = High Pressure System Where to find the HDP’s Production and Serial Number Check for open electrical circuit between rail sensor and DME; ‘submit TC case for rail sensor replacement if necessary; Note: default value appears as 265bar, when sensor deffective / open circuit DC HPS 29E2 -No- Check for open electrical circuit between HDP and DME; replace components if necessary DC HDP HARNESS ‘Submit TC case for HDP replacement Ignore fault entry, delete fault memory SI B12 11 10 DC HDP VCV Yes- EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary ‘Submit TC case for HDP replacement DC EKP Check battery voltage; check starter; check crank shaft and camshaft sensors; repair if needed No trouble found -► EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary DC EKP OK ‘Submit TC case for HDP replacement DC HDP 2FBF DC OTHER LC No -Repair was needed at battery, starter, crankshaft or camshaft sensors- Rail Pressure Sensor Plausibility Yes- Check HP sensor; make sure car was sitting more then 15min; follow diagnostic request to compare LP to HP sensor values; use manual fuel pressure gauge for LP side. Values must not differ more the +/-3 bar; replace HP sensor if necessary Important note: in case the HP sensor value is higher then 9bar, release the pressure by slightly loosening the connection between the injector and the rail and repeat the above check again; in case of repeated failure ‘submit TC case for HP sensor replacement DC HPS 29F1 OK ‘Submit TC case for HDP replacement Create and Submit TC-Case where applicable. Readapt DME and perform test drive on page 1. Recheck fault memory after test drive, if clear, return car to customer 33 Ignition Management SI B 12 11 10 N54, N54T, N55 - Diagnosis for HDP High-pressure Faults Check fault memory EKP Module Low Pressure Sensor DME Low Pressure (LP) System Low Pressure Sensor DME High Pressure (HP) System No DFT - Fuel System N55 F07, F10 Page 2 Information: CCC message „fuel pump defective' 1 or engine does not run at all EKP function check according to ISTA EKP test modules; ‘submit TC case for EKP replacement if necessary DC EKPM Yes Add fuel, delete fault memory For Your Information Definition of the Jong crank" complaint: the engine is cranking up to about 3-4 seconds, before it starts quickly LP = Low Pressure System HP = High Pressure System Where to find the HDP’s Production and Serial Number Replace LP sensor, DC LPS Yes Yes Check LP sensor. Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 7.7 bar, the LP sensor is faulty and must be replaced. OKj~ J DC LPS EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary DC EKP Check for open electrical circuit between rail sensor and DME; ‘submit TC case for rail sensor replacement if necessary; Note: default value appears as 265bar, when sensor deffective / open circuit DC HPS 29E2 -No- Check for open electrical circuit between HDP and DME; replace components if necessary T ‘Submit TC case for HDP DC_HDP_VCV replacement DC HDP HARNESS Update 1-Level With ISTA/P 37 or newer If 1-Level < Fxxx-10-03-502 Yes- -Yes- Ignore fault entry, delete fault memory SI B12 11 10 1 Check LP sensor. Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 7.7 bar, the LP sensor is faulty and must be replaced. OK J DC LPS EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary "oi<~ _I_ ‘Submit TC case for HDP replacement DC EKP Update 1-Level With ISTA/P 37 or newer If 1-Level < Fxxx-10-03-502 No trouble found ,long crank" complaint without fault entry, possibly with info entry 0x11A401, 0x11B501,0x11B601 Yes- Check LP sensor. Actuation of the electric fuel pump (EKP) for approx. 20 seconds via ISTA. Read the value from the LP sensor via ISTA during EKP operation after approx. 15 seconds. If the value displayed is more than 7.7 bar, the LP sensor is faulty and must be replaced. OK f J DC LPS Check battery voltage; check starter; check crank shaft and camshaft sensors; repair if needed EKP function check; follow ISTA test module; ‘submit TC case for EKP replacement if necessary DC EKP OK No ‘Submit TC case for HDP replacement No DC OTHER LC Update 1-Level With ISTA/P 37 or newer DC HDP 2FBF -Repair was needed at battery, starter, crankshaft or camshaft sensors- Rail Pressure Sensor plausibility Yes- Check HP sensor; make sure car was sitting more then 15min; follow diagnostic request to compare LP to HP sensor values; the values must not differ more the +/-3 bar; replace HP sensor if necessary Important note: in case the HP sensor value is higher then 9bar, release the pressure by slightly loosening the connection between the injector and the rail and repeat the above check again; in case of repeated failure ‘submit TC case for HP sensor replacement DC HPS 29F1 OK ‘Submit TC case for HDP replacement Update 1-Level With ISTA/P 37 or newer If 1-Level < Fxxx-10-03-502 Create and Submit TC-Case where applicable. Readapt DME and perform test drive on page 1. Recheck fault memory after test drive, if clear, return car to customer 34 Ignition Management