A "chirping" noise coming from the engine compartment at idle may be from the A.I.R. check valve in the air supply line to the catalytic converter (see Figure 1). This noise may be evident when the vehicle is fully warmed up.
To determine if this noise is originating from the check valve, pinch off the rubber hose between the check valve and the air management valve. If the noise stops, the check valve should be replaced.
The original check valve (Part Number 22017478) should be replaced with check valve, Part Number 22036195.
The chart below lists the vehicles and engines this information applies to:
V.I.N. ENGINE ENGINE CODE VEHICLE APPLICATION 1981-82 1983 Grand Prix/Bonneville Parisienne ------ ------------- --------------------------------- 3.8L V6 - LC3 9 1983 5.0L V8 - LG4 H H 1982-83 1982-83
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.