P0278

DTC P0263, P0266, P0269, P0272, P0275, P0278, P0281, or P0284

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0263
- Cly 1 Balance System

DTC P0266
- Cly 2 Balance System

DTC P0269
- Cly 3 Balance System

DTC P0272
- Cly 4 Balance System

DTC P0275
- Cly 5 Balance System

DTC P0278
- Cly 6 Balance System

DTC P0281
- Cly 7 Balance System

DTC P0284
- Cly 8 Balance System

Circuit/System Description

The engine control module (ECM) monitors changes in crankshaft speed using input from the crankshaft position sensor. The ECM adjusts the fuel delivery to each cylinder in order to minimize crankshaft speed changes. If the ECM identifies a cylinder or cylinders requiring an excessive adjustment of fuel in order to maintain the correct crankshaft speed, a DTC will set.

Conditions for Running the DTC

* DTCs P0117, P0118, P0335, P0336, P2146, P2149, P2152, P2155 and P062C are not set

* The ECT is more than 40°C (104°F).

* Engine is running.

* The engine RPM is between 600-2,700 RPM.

* The calculated fuel rate is between 15 mm3 and 90 mm3.

* DTC runs continuous when the above conditions are met.

Conditions for Setting the DTC

The fuel injector balance correction is greater than the calibrated limit.

Action Taken When the DTC Sets

DTCs P0263, P0266, P0269, P0272, P0275, P0278, P0281 and P0284 are Type B DTCs.

Conditions for Clearing the DTC

DTCs P0263, P0266, P0269, P0272, P0275, P0278, P0281 and P0284 are Type B DTCs.

Reference Information

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON.

2. Observe the DTC information with a scan tool. Verify no other DTCs are set.

• If other DTCs are set
refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

• If no other DTCs are set

3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If DTC resets
Refer to Circuit/System Testing.

• In DTC does not reset

4. All OK.

Circuit/System Testing

Note: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Perform a engine compression test. Refer to Engine Compression Test Testing and Inspection.

• If engine compression is not within specifications
Repair as necessary.

• If engine compression is within specifications

2. Refer to Fuel Injector Diagnosis Fuel Injector Diagnosis.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.