Temperature Gauge - Perceived Engine Overheating

91pontiac11

Bulletin Number: 91-8-15
Reference Number: 138303
Publish Date: 6/91


Subject: PERCEIVED ENGINE OVERHEATING CONDITION (DIAGNOSIS/INSTALL NEW GAUGE)


Models
Affected: 1988-91 LEMANS


The purpose of this new gauge in production on the 1991 LeMans is to address customer comments of engine overheating.

The new gauge repositions two of the graduations on the face of the gauge. The positioning of the "Midpoint" and the "Three-Quarter" graduation have been moved upward slightly. The revised position of the "Three-Quarter" graduation will allow the temperature needle to be positioned at or near that graduation rather than above it during normal engine operating temperatures.

If a customer comment is received for engine overheating, a complete cooling system inspection must be performed. This includes verifying that the engine operating temperature is normal using a "Tech 1" diagnostic computer scan tool. If no apparent reason for the overheating can be found, then the new gauge P/N 96137541 may be installed in place of the existing gauge. The standard temperature gauge replacement procedure as found in the LeMans Service Manual should be followed.

Part is currently available from GMSPO.

IMPORTANT: After installing the new temperature gauge, the customer should be advised that it is normal for the temperature needle position to be at or near the "Three-Quarter" graduation during normal engine operation.

Usage of the new P/N gauge became effective in production with VIN MB310798 for the 1991 LeMans.

Use applicable labor operation.