Thermostat issue on 95 Lumina

[Mark72]

Let me describe this and see what any of you think this problem could be on this 1995 Chev Lumina that has 178k on it. When it is warm to hot out (today it is 78 degrees) and I’m city driving or idling along, the thermostat gauge in the car goes up to ¾ and acts likes it’s about to redline but doesn’t. Then it will stick there for several minutes before it VERY slowly starts going back to the halfway mark where it normally would register.
Any of you think this would be a thermostat issue? Car is running smooth, no shudder, no nothing.

 

[artificialist]

See if your cooling fans come on and off normally. Sometimes cooling fans operate on a different circuit than the engine temp sensor, causing cooling fans to start at the wrong time.

 

[Chris142]

Sounds normal to me. All those cars get right up to the Red before the fans come on. They are supposed to come on @ 226 degrees.

 

[Mark72]

the fan will not come on until it's up to 3/4 of the way

 

[SteveSRT8]

no offense but the factory gauges in that car are nearly worthless.

Hook up a real gauge or use an infra red thermometer to get the actual temps.

 

[Mark72]

Originally Posted By: SteveSRT8
no offense but the factory gauges in that car are nearly worthless.

Hook up a real gauge or use an infra red thermometer to get the actual temps.


No offense taken. and yes, I have heard that before. also, the fan on the right side never comes on unless the AC is running. why would that be? should it not come on in conjunction with the left one even if the compressor is not on when the motor gets hot enough?

 

[meep]

I saw a 96 doing this new. if the temp switch on those fans is mechnanical it could be getting tired.

 

[mechtech2]

Could be a faulty sending unit - weird or sluggish.
Oddball water pump impeller problems - loose or corroded.
Fan control sending units.
Plugged cooling system - radiator or passages.