COMPUTER COMMAND CONTROL FALSE SETTING OF CODE 24

Subject: FALSE SETTING OF CODE 24 (VEHICLES EQUIPPED WITH 2.8L V6)

A check engine light may be turned on and a Code 24 stored when the throttle is opened and the road speed sensor continues to read zero (0) for five (5) seconds.

This can occur under conditions such as trying to get going up a steep incline, driving the vehicle in reverse or when an engine is loaded to stall speed against the brakes.

As an interim 1982 release, a new ECM, which has ISC components removed, has entered production for the 2.8L V6 engine. This new ECM incorporates a calibration revision which expands the Code 24 timer from five (5) to sixty seconds.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.