Sticky Thermostat?

[crossman]

For the past few weeks, I have noticed that when I start up my Explorer and drive it, the temp gauge will go up like it is supposed to, but it will go up to "AL" in NORMAL, stay there for a minute or so, then drop right down to "NO" and stay right around there. Could the thermostat be sticking closed, thus causing the initial high temp? The thermostat in there now is about two years old and was a 190-195 degree t-stat.

 

[Michigander]

It could be the thermostat. I don't know about the pre 95 models. Does your temp gage have temp readings on it or just a redline at the tops? Just pull it and replace it... it's only about $8 plus coolant if you do it yourself and will help the life of the Explorer.

After you take it out, go inside, boil some water and throw it in, if it doesn't pop open the instant it is in the water, it was defective.

 

[fixer]

my thrermostat was doing basicly the same thing... bouncing all over like a teen-age cheerleader on a trampoline and making the "check guage" light flash. i dropped a few bucks at AutoZone for a thermostat, gasket and some coolant additive that's suposed to prevent rust, lubricate the waterpump, make your hair silky and your breath sweet smelling. after a few minutes of twisting wrenches in both popular directions, no more funky problems.

i had to replace the little bit of coolant i lost, then run the engine for a few minutes and top it off again.... musta had a bubble in there somewhere.

i also changed the serpentine belt while i was under the hood... but that was not part of the problem, just PM.

 

[crossman]

The temp gauge in my Ex. just has the NORMAL type gauge with a red line at the top of the gauge above "L". I'll just change the t-stat to see if that fixes the wacky gauge readings. Thanks for the help!

 

[Blake D]

What is the outcome? Was it just the gauge?