Overheating Continues

shotgunslade · #1 08-21-2006, 06:02 AM

After my Friday track day, I though I had my overheating problems fixed, but a new gremlin has arisen to give me grief. I noticed it first on Sunday. Went to the car wash, and the temperature, right after starting, with only in town driving, rose right up to the red bar. After a little bit, it dropped down to mid level, stayed there, and then a little while later rose up to the red line. Putting the AC on and off seemed to have some effect, but its not consistent. Sometimes, turning the AC off or on would initiate a change, other times not. All of this is occuring at very low rev's, in-town, modest acceleration. The fans are running.

I read all of the threads about head gasket blow-by, boiling the coolant. Thought that might apply because of my experience at the track. But, this isn't consistent with that. It is too off and on. Normal, then hot, then back to normal again. No in-between and not linked to accelerator use. I'm betting on a balky thermostat. Have ordered one, will change it, but will get the HC coolant test at the same time.

Any thoughts?

Manarius · #2 08-21-2006, 07:35 AM

I think that you might have a semi-block in one of the coolant lines. That would account for the pegging of the redline, only to come back to the middle again.

immortal_suby · #3 08-22-2006, 07:19 PM

mine was pretty inconsistent with a bad head gasket. some days I had no problem. some I overheated quickly. the only thing that was consistent is that it got worse over time.

dwd1985 · #4 08-22-2006, 07:23 PM

I would agree that it sounds like a sticky thermostat. Mine did that when my thermostat was heading out. Replacing it fixed the problem right away.

msvx95 · #5 08-23-2006, 04:49 AM

Bad thermostat would cause the up and down fluctuation....Head gasket would peg the needle and stay there after car is warmed up.

SilverSpear · #6 08-23-2006, 04:58 AM

Change the termostat first... but he also could be facing a water pump failure or a bad Rad.

immortal_suby · #7 08-23-2006, 06:43 PM

Quote:

Originally Posted by msvx95

Bad thermostat would cause the up and down fluctuation....Head gasket would peg the needle and stay there after car is warmed up.

It might depend on where the head gasket fails.
Mine had no oil/coolant mixing or loss. I was just overheating the coolant from blow by and that was causing boil over into the expansion tank.

But - if I drove it easy it could heat up and cool down. Running the heat on high would usually keep it cool. It wouldn't stay overheated unless I beat on it or the coolant got low. Alot of times I could take long highway trips with no problem and then when I stopped or slowed down for traffic the overheating started.