Hi Folks,

For a while now the temp gauge in my 82 240D auto has been screwy.

I believe the gauge is giving false high readings. Everything seems to operate as normal until I have driven for roughly 20-30 minutes. Then the gauge begins to creep up to the 100 degree mark. If i tap on the gauge cluster the needle will drop down to the normal operating temp range right above 80 degrees.

Today on my drive after some long hill climbs I noticed the gauge was reading around 100, if I tapped on it it only moved slightly making me unsure if the motor was actually running too hot or not.

I checked the gauge against my inferred thermometer to test it accuracy and the hottest point on the engine was 78 degrees, lower coolant hose wasn't even hot, leading me to believe the motor wasn't warm enough to warrant the thermostat opening.

Is it possible that higher engine speed means a more intense electrical signal is being sent to the gauge cluster making the gauge go haywire?

I believe the engine is operating within the correct temp range but would like to be able to rely on the temp gauge.