E046

Diagnostic Chart.:

PCM Wiring:

DESCRIPTION:

The PCM/ECM controls right bank fueling based on the right side oxygen sensor and left bank fueling based on the left side oxygen sensor. Code E046 sets when the left bank fueling differs (richer or leaner) than right bank fueling.

TEST CONDITIONS:

Continuously.

FAILURE CONDITIONS:

Left bank fuel control block learn values differ from right bank fuel control block learn values by more than 15 counts for 10 minutes.

ACTION TAKEN:

1. PCM/ECM turns on "SERVICE ENGINE SOON" telltale.

NOTES ON FAULT TREE:

1. The oxygen sensor must be able to generate sufficient voltage and cross counts to cause the system to go into closed loop operation.

2. Contamination of the oxygen sensor can slow the reaction time of the sensor. Trouble codes E013, E017, E042, E043, and E045 are designed to detect a sensor fault. The slow reaction time of the sensor may cause a driveability problem.

Likely causes of code E046 are:

1. Lean or faulty injectors on one side of the engine.
2. Cracked or fouled spark plugs.
3. Exhaust or intake manifold leak.