coolent temp problem (kinda long)

[awdornowd]

Ok I've looked and looked and can't seem to find the answer I need. My car seems to be running hot. It starts and idols perfectly. When the car warms up the gauge is right where it's supposed to be (right at or just below the middle). Well after about ten minutes or so of stop and go traffic the gauge starts going up VERY slowly at lights, sometimes just sitting alittle above halfway. Then when I start going again it goes back down to where it should be but after driving alittle more it goes down less and less. It never goes above the little symbol on the gauge though but it does go to the very top of it. Even on the highway it runs hotter then it should. Then when I get off and slow down it goes down just alittle. The fan works and I replaced the radiator cap and the engine temp gauge unit sensor. I don't see boiling of the antifreeze either. Does anyone have an idea of what this could be? Oh and this is all without the A/C on (doesn't work). Thanks for any help I can get.

 

[dmak]

maybe water pump. when's the last time did a rad flush and change the coolant?

 

[versatilx1]

maybe his thermostat

 

[awdornowd]

I'm not sure when it was changed last but it still looks brand new. This problem came all of a sudden too.

 

[Talesin]

Not likely to be the thermo. Mine went bad, and it ran super-cold.

Check your water pump, ask them to test your radiator. If you bought a car and didn't get the timin belt and water pump changed first thing... well.. do it now, if the belt hasn't snapped.

 

[rocketjr]

A good flush and re-fill couldn't hurt. The thermostat could still be bad. In Talesin's case it got stuck wide open. That isn't always the case. It can get stuck closed or somewhere in the middle or just have enough gunk on it that it catches while it opens. If it were me I would drain the system replace the thermostat (cheap item anyway) and refill making sure that you don't leave any air in the system....air bubbles can cause weird temp fluctuations. Good luck..