tonight on the way home my temp guage went all the way up. 35 degrees outside, cruising along out in the country. I pulled over, shut it down, popped the hood, the radiator itself was cool, the hoses were warm but not really hot, the engine was hot but not really hot, I could put my hand on the valve covers without burning myself. I grabbed a bunch of rags and opened the radiator cap (I know bad idea) and it hissed about like when you open a soda can, that was it. the radiator was full. I started the car back up, the temp guage was halfway, sat for a minute, temp guage didnt move, as soon as I pulled out, the guage went all the way back up. I really dont think I overheated it, but I'm not sure. does it sound more like the guage? or the sender?

As long as the gauge seems to function throughout it's travel, it is most likely the sender(and easier to fix too), most gauge malfunctions I have came across have been senders or wiring related.

My 1st thoughts on this would be defective T-stat, as the radiator was cool, hoses warmish, and engine hot. In my book, that means bad T-stat.

kinda the same thing here , temp gauge would go up into the red and stay there 30-40 sec, then drop down , changed t-stat fixed problem ,temp gauge stays steady 1/2 way

...I could put my hand on the valve covers without burning myself. I grabbed a bunch of rags and opened the radiator cap (I know bad idea) and it hissed about like when you open a soda can, that was it.

No gush of coolant? How quickly did the temp guage rise? "Really hot" should have given a gush, and it takes time to heat all of that water and aluminum, so the gauge shouldn't be quickly changing (i.e. 1-5 seconds to go from mid to hot is too quick, 10-30 seconds is more reasonable but still rather fast). If too quick, the sender/wiring/guage is probably malfunctioning.

 

Just for grins and to be sure, I would replace the sender and check the visible wiring for worn insulation. It sounds encouraging that the engine was not too hot to touch, but that is kind of subjective. (It would be informative to me if I did it, but only you know you.)

 

DON'T PANIC!

 

(Sorry... a little Douglas Adams advice/humor.)

 

Pat

I pulled the Tstat out just to check, and it still did the same thing, maybe the radiator was so cool because it was 35 degrees out

Hey Roobaflu, did you find the cause of this, get it straightened out?

 

Just wondering.

Pyro

i was over there yesterday painting the sedan and noticed the intake bolt wasn not tight. we removed it pulling the motor to take off the ground wire. i pointed that out and vincent tightened it, said the wire runs to the temp sensor. but i dont know if that fixed the problem, but the syptoms sounded more electrical than mechanical

 

 

vincent, how is she doing now? hope that fixed ya!

that didnt fix it :\ I thought for sure that would have done it. But I started the car after it had been sitting overnight, and the gauge was reading halfway at startup, that CANT be right, lol

hmm. the sender must be whack. i took the one off my sedan for an aftermarket unit, i can bring it when i come back from ohio.