DTC'S 91-98, Cylinder Balance Fault: Notes

PCM is able to increase and decrease amount of fuel to each cylinder to provide smooth idle operation. DTCs 91-98 will set if too great of a fuel adjustment is required. These DTC's indicate a possible mechanical or fuel delivery problem.

DTC's 91-98 will set when: 

• Engine idling.
• Coolant at operating temperature.
• Cylinder fault constant.
• Fuel correction amount exceeds defined limits (internal to PCM) for 2 seconds.

PCM will default to rough idle. DTC will be stored as a current and history code, but will not turn on MIL.

1. This step will determine if there is a specific cylinder at fault by using cylinder out (INJ. BALANCE). If a specific cylinder is not responding to cylinder cutout (RPM drop), this cylinder should be considered a suspect cylinder.
2. This step will determine if a faulty duel mass flywheel is setting multiple cylinder balance DTCs.