kwikracer

My 94 gs with 267k mi. is overheating... again. I've replaced t-stat, head gasket, resurfaced head, radiator cap, water pump fan clutch and temp sender which goes to the gauge within the last year.

I'm hoping it's the temp sender. Definitely hoping its not the head gasket.

When I got the car with 184k mi and it ran perfect, whenever I'd start it from sitting overnight even on the hottest days the temp gauge would be slightly below the lowest line, the "C" and take a good 4 minutes to get to normal operating temp. Now even after sitting for the weekend when I first start it up it will be slightly above the "C" line and will reach normal operating temp in 2 minutes. Which I think is kinda weird.

So with the A/C off it will get to the next line up from normal temp or slightly above it under load. But never has it gone to the "H". When I turn on the A/C it'll bring it down to normal while idling or coasting and to the next line from normal under load. So the A/C actually helps cool it down a bit.

I've verified my fan clutch is working and I don't seem to be losing coolant. There's no oil mixed with coolant or vice versa or bubbling coolant.

I was hoping maybe the sender came off an ES300 mistakenly which maybe runs cooler than the GS which in turns sends an overheating signal to the gauge when it's actually normal. (Am I reaching here?)

Any ideas???

Nixspeed

All gauges and sensors will have variables in voltage so you may be right on there. If while overheating you can check with a temp gun or something or just replace the sensor with a correct GS model.