On 1988-89 Pontiac 6000 Series cars with 2.8L engine and optional analog gage package, the temperature reading may show a reading to the right of center (220 degrees). While there are no other indications of overheat, and the engine is not actually overheating, the reading may cause customer concern.
----------- 1. Attach a scanner to the ALDL connector. While driving the vehicle at normal highway speed, verify that the engine temperature shown on the scanner does not exceed 220 degrees F, or 105 degrees C. If this temperature is exceeded, look for the cause of actual engine overheat.
2. Turn ignition to "Off" position.
3. Locate the temperature sender in the rear cylinder head, near the left end of the head. Disconnect the sensor. Install a 20 ohm, 1/4 watt resistor in the wire harness to the sensor (obtain the resistor from a local electronics store) . There are two wires in the connector - one for the sensor, and a black wire for the temperature lamp switch. Install the resistor in the colored wire. Be sure to solder the connections and tape the wire. Reconnect the sensor.
4. Road test to insure that the gage now operates properly.
Labor Operation : T1485 Labor Time : 0.8 Hours
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.