When cold starting my 92 the temperature gauge climbs slowly as it warms up until it hits the upper peg. It immediately (2 seconds) returns to the normal reading point as soon as the needle hits the upper peg. I've replaced the temperature sensor and thermostat and it made no difference at all. My mechanic put a special sensor on the radiator and said it's not really overheating so he thinks it's the temperature gauge itself. The rate at which the gauge climbs to the peg does change with ambient temperature (slower in cold weather).
Has anyone ever seen a gauge ever fail in this way? It's a real pain to get in there and change it and I'd like to be sure it's the gauge before I tackle that. Is there any way I test the gauge by backfeeding the sensor connector ?
Gary