nsoftic

I have 1997 A4 Q (12 valve V6)
Several times my check engine light came on with the same message indicating Engine Collant Temp Sensor. The message was as fllows:
16500 - Engine Coolant Temp. Sensor (G62): Implausible Signal
92-00 - Unknown Error Elaboration

I went ahead and replaced the Engine Coolant Temp sensor.
However the light came on again. Here is the behaviour I am experiencing.
When it is cold and I am driving on a highway the Temp Gauge keeps going from very low to middle of the scale. When it is not cold or I am driving in city with stop and go the temp gauge stays in the middle of the scale. Also the Check Engine light comes on at the moment the temperature gauge drops from near middle to bottom of the scale.

I am confused in what could be happening. Could anybody give me a hint at what else should I be looking at. Is there another relay that can be affected by the outside temperature that could cause errored readings from temp sensor.

Any help would be greatly appeciated.

Thanks,

Nedim

markbradford

Check the wiring from the sensor for a short.

NCAudiA4

Had my coolant temp sensor changed it took me over 200 miles and 4 days of various driving...from rush hour to interstate to around town....

nsoftic

Not sure what do you mean by resetting itself, but the check engine light went on first time I took it out on a highway (after some 30 mins). I have not reset it since allthough I drove it some 600 miles mostly highway.