Noticed this today while driving on the highway 65-80 mph.
For a few minutes the gauge would go from 3 pm reading to lets say 4 pm reading (but not all the way to bottom) and then it would come back?
Is it something I should be worrying about? This is the first time i noticed this. Usually the gauge would stay at 3 pm once the engine warms up.
What could be the problem? thermostat? coolant sensor?

thanks for your advice


the car in question: 95 855 192400 K miles manual trans N/A

I hope you have an OEM thermostat. If not, replace it.

I could understand the gauge acting like that on really cold days with the engine just begining to warm up when you get on the Interstate. The coolant in the radiator would be really cold when the thermostat opens, and the sensor gets a wash of cold fluid. Even then, the fluid needs to go through the block before it goes past the ECT sensor.

Schedule some time to replace the antifreeze, thermostat, and ECT sensor. Before winter makes it a hard, knuckle busting job. Just get OEM parts.

Klaus
--
Common sense trumps a PhD

A,

The circuit has a component (don't that what it's called) to even out moderate temperature variations.

IPD, ipdusa.com, used to sell a repair kit to bypass this component.

Probably not an engine problem if the temperature stays at mid-point after warm up.

Check the archives.

Bryan