Last week, my temp gauge started acting very weird. It would read normal then "bounce" to pegged in the red zone. Then bounce back. Or not. Sometimes it went straight to pegged when I started the car (cold) in the morning, sometimes it worked normally for a few minutes then pegged red, or bounced. It sure looked like a faulty Temp Sending Unit.

My local auto parts store didn't have a temp sending unit for my car in stock, so I figured I'd order it (and a thermostat) online. But I procrastinated. (I'm good at that.) And a funny thing happened. It stopped pegging - it's back to acting perfectly normal during my 25 minute drives this morning.

Has anyone else encountered this?

(1994 Volvo 960 Wagon.)

 

Haven't had it happen to my 850 but it sounds like you might have a nicked wire causing an intermittent short or bad connection at the sensor.