GM Service Manual Online
For 1990-2009 cars only

UNSTABLE ENGINE IDLE STALL OR CODE 35

MODELS AFFECTED: 1987-88 CENTURYS WITH LB6 2.8L V-6 ENGINES (VIN CODE W) 1988 REGALS WITH LB6 2.8L V-6 ENGINES (VIN CODE W)

Some 1987-88 Buicks with a 2.8L engine (VIN Code W) may exhibit driveability concerns such as:

- Engine not continuing to run

- Unstable idle

- Check engine light with stored Code 35

These symptoms may be due to customers starting their vehicles while their foot is resting on the accelerator pedal, or may be due to the cruise control cable being adjusted too tight (on vehicles equipped with cruise control). If customer comments are received concerning the aforementioned driveability concerns, it is recommended that:

1. The cruise control cable be checked for proper adjustment (reference cruise control cable adjustment procedure in the Service Manual, Section 9, and

2. The throttle position sensor (TPS) be adjusted to obtain 0.62 - 0.72 volts (NEW SPECIFICATION) (reference TPS adjustment procedure in Section 6E3 of the Service Manual).

Use applicable labor time and operation number.

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.