SERVICE ENGINE SOON LIGHT FALSE CODE 32

Model and Year: 1986 CORVETTE WITH CAST IRON CYLINDER HEADS (VIN CODE 8)

TO: ALL CHEVROLET DEALERS

This bulletin applies to Corvettes equipped with cast-iron cylinder heads only (VIN 100000 to 119016).

Most Code 32 (EGR system failure) can be corrected by using the diagnostic chart shown in your 1986 Corvette Shop Manual (Page 6E3-A-49). Occasionally when the vehicle is not corrected by using the above diagnostics, it will be necessary to inspect the right hand intake manifold gasket. The gasket must have a metal insert covering the EGR passage in the head. If the insert is missing, the EGR gases have dual paths to follow. This causes the temperature switch to read low causing the false Code 32. If the right hand intake gasket on the engine is missing the metal insert, a gasket with the metal insert is to be installed. Below is a picture showing the R.H. gasket and the correct position of the metal insert.

Use applicable labor time and operation numbers.

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.