P0272-CYLINDER 4 CONTRIBUTION/BALANCE
P0272-CYLINDER 4 CONTRIBUTION/BALANCE
For a complete wiring diagram, refer to the Wiring Information.
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When Monitored:
With the ignition on.
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Set Condition:
The Powertrain Control Module (PCM) is unable to stabilize fuel quantity in cylinder 4.
Possible Causes |
|---|
| ENGINE COMPRESSION |
| FUEL INJECTOR QUANTITY |
| FUEL SUPPLY CONTAMINATION |
| INJECTOR LEAKAGE |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
| NOTE: | If the PCM detects and stores a DTC, the PCM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the scan tool at the same time the DTC is displayed. |
| NOTE: | Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for an active DTC. |
| 1. | With the scan tool, erase PCM DTCs. |
| 2. | Test drive the vehicle and attempt to duplicate the problem. |
| 3. | With the scan tool, read PCM DTCs. |
Did this DTC return?
Yes
- Go To 2
No
- Perform the INTERMITTENT DTC diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
2. CHECK FOR FUEL CONTAMINATION
| 1. | Use the service information and inspect the fuel supply for contamination. |
Is the fuel contaminated?
Yes
- Flush the fuel system in accordance with the service information.
- Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Go To 3
3. CHECKING THE SUPPLY SIDE FUEL DELIVERY SYSTEM
| 1. | Perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic procedure. (Refer to 29 - Non-DTC Diagnostics/Drivability - Diesel - Diagnosis and Testing) . |
Were there any problems with the Fuel Delivery System?
Yes
- Repair as necessary in accordance with the service information.
- Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Go To 4
| 1. | Ignition on, engine off. |
| 2. | Perform the Cylinder Compression Test in accordance with the service information. |
Is the cylinder compression within specification for all cylinders?
Yes
- Go To 5
No
- Repair as necessary in accordance with the service information.
- Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
5. CHECK THE FUEL INJECTOR CIRCUIT RESISTANCE
| 1. | Turn the ignition off. |
| 2. | Disconnect the PCM harness connectors. |
| 3. | Disconnect each Fuel Injector harness connector. |
| 4. | Measure the resistance of each of the Fuel Injector Control circuits between the Fuel Injector and PCM harness connectors. |
Is the resistance below 5.0 Ohms for each measurement?
Yes
- Check the intake system for air leaks that could affect this cylinder. If found, repair intake system leak as necessary. If o.k. replace the Fuel Injector.
- Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).
No
- Repair the Fuel Injector circuit that measured above 5.0 Ohms for an open or high resistance.
- Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).