- LC - DODGE CHALLENGER - 6.L V8 SRT HEMI MDS P9B-BANK AIR-FUEL RATIO IMBALANCE For a complete wiring diagram, refer to the Wiring Information. BATTERY A0 0 87 87A RELAY- RUN/ START ASSEMBLY- POWER DISTRIBUTION CENTER FUSE A FUSE 78 0A CONNECTOR- STAR CAN C DASH 8 C CAN C (+) CAN C (-) A9 RD F9 PK/LG D7 TN/WT C D8 YL 9 8 9 8 96 FUSED B(+) O / O / 57 C FUSED IGNITION SWITCH OUTPUT (RUN-START) CAN C (+) CAN C (-) O / O / 9 0 7 O / SUPPLY 8 O / 9 O / O / 96 C MODULE- POWERTRAIN K99 BR/LG K DB/LB K90 BR/DG K DB/LG K99 BR/VT K99 BR/WT K DB/YL K90 DB/DG K DB K99 BR/GY O / O / / O / O / / O / O / / O / SUPPLY O / / 8009906
Theory of Operation The purpose of the Cylinder Imbalance Detection diagnostic monitor is to detect an air/fuel ratio imbalance between the cylinders across an entire cylinder bank. NOTE: Although it does not indicate as such, this fault will set because a specific cylinder on this bank is out of balance with the other cylinders. The fault may not be easily noticeable to the technician. During diagnosis, it is necessary to pay close attention to small differences between the cylinders during each of the test steps. This imbalance can be caused by a number of different malfunctions including but not limited to: Intake Manifold leak at a specific cylinder Fuel Injector problem Variable cam lift failure Camshaft/Valvetrain problems Ignition system problems at a specific cylinder Engine mechanical problems relating to cylinder combustion at a specific cylinder The Cylinder Imbalance Detection requires that the Upstream O Sensors are capable of operating at high frequencies, since an aged O Sensors response capability at a higher frequency range can be degraded. Therefore, before this monitor can become active, the O Sensor High Frequency Response monitor is performed to see if the sensor is even capable of detecting an imbalance. Once active, the Cylinder Imbalance Detection monitor matches up the Upstream O Sensor signal with the corresponding cylinders on that bank. Each cylinder is monitored and adjustments are made as needed for each cylinder to correct an air/ fuel ratio imbalance. If an individual cylinder reaches a calibrated adaptation threshold (5%), the diagnostic monitor will be considered failing. When Monitored and Set Conditions When Monitored: This diagnostic runs continuously when the following conditions are met Engine run time of 90 seconds. Engine Coolant Temperature (ECT) is between 70 C - C (58 F -5 F). Closed loop fuel control. Engine speed between 000-700 rpm. Calculated engine load between 0-90%. The Upstream O Sensor high frequency diagnostic monitor has run and passed this trip, and PD is not present or pending. For flex fuel vehicles the Fuel Adaptive Learned must be completed. Set Conditions: The Powertrain Control Module detects that one of the cylinders on bank has an air/fuel ratio imbalance of 5% when compared to the other cylinders on the same cylinder bank. Default Actions: The MIL light will illuminate.
Possible Causes INTAKE MANIFOLD LEAK AT A SPECIFIC CYLINDER ON BANK FUEL INJECTOR ISSUES AT A SPECIFIC CYLINDER ON BANK IGNITION SYSTEM ISSUES AT A SPECIFIC CYLINDER ON BANK CYLINDER COMPRESSION IMBALANCE CARBON BUILD UP VARIABLE VALVE TIMING ISSUES VALVE TRAIN ISSUES Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding. (Refer to 8 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure). CHECK FOR AN ACTIVE DTC. Start the engine.. Allow the engine to reach normal operating temperature.. Test drive the vehicle in accordance with the when monitored conditions.. With the scan tool, read DTCs and record on the repair order. Is the DTC active or pending? Yes Go To No Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 8 - DTC-Based Diagnostics/ MODULE,. CHECK FOR AN INTAKE MANIFOLD LEAK AT A SPECIFIC CYLINDER ON BANK. Check for the following conditions: Intake manifold seals leaking at a specific cylinder. Intake plenum leak at a specific cylinder. Warped/cracked Intake Manifold or plenum. Vacuum leak at a Fuel Injector O-Rings. Yes Repair the vacuum leak(s) as necessary in accordance with the Service Information. No Go To. CHECK FOR FUEL INJECTOR ISSUES AT A SPECIFIC CYLINDER ON BANK. Check for the following conditions: Correct Fuel Injector voltage supply. Correct Fuel Injector control circuit operation.
Correct Fuel Injector operation (spray pattern). Yes Repair Injector circuits or injector spray pattern issue as necessary. No Go To. CHECK THE CYLINDERS ON BANK FOR LOW COMPRESSION AND IGNITION SYSTEM ISSUES. Perform a cylinder compression and/or cylinder leak down test on each cylinder on bank.. Check the ignition system for the following conditions: Correct voltage supply at each Ignition Coil. Correct control circuit operation at each Ignition Coil. Spark Plugs are matching and are equivalent to OEM specifications. Correct Spark Plug gap. Ignition Coils and Spark Plugs for signs of carbon tracking. Ignition Coils for signs of damage. Were any problems found? Yes Repair the Ignition system primary or secondary circuits or components as necessary. No Go To 5 5. CLEAN THE CARBON FROM THE COMBUSTION CHAMBERS AND CHECK DTCS. Using the Mopar Combustion cleaner, de-carbon the engine.. After driving and clearing the combustion cleaner from the engine, erase DTCs with the scan tool.. Test drive the vehicle in accordance with the When Monitored conditions.. With the scan tool, read DTCs. Did the DTC return? Yes Go To 6 No Decarbonizing the combustion chambers repaired the condition. 6. CHECK FOR VALVETRAIN AND MULTIPLE DISPLACEMENT SYSTEM (MDS) ISSUES. Check the valve train for the following conditions: Correct operation of the MDS Control Valve Solenoids. Correct operation of the Deactivating Roller Lifters.
Broken, worn or improperly installed valve springs. Improperly installed Deactivating Roller Lifters. Worn Camshaft lobes. Broken, worn or damaged MDS control valve solenoid wiring. Yes Repair the MDS or Valvetrain components as necessary. No 7 7. CHECK FOR INFORMATION RELATED TO THIS DTC. Check for related Service Bulletins and any other official OEM documentation related to this DTC. Were any related Service Bulletins or official OEM documentation related to this DTC available? Yes Repair the condition by performing the related procedures outlined in the Service Bulletin or official OEM documentation. No Anything that can cause an air/fuel ratio imbalance in an individual cylinder will cause this DTC to set. Verify all of the items in this test and any other mechanical items that could cause this DTC to set. 5