Getting hot....then cooling back down

saltfish · Post by **saltfish** » Wed Aug 29, 2007 1:27 pm

I've got a '92 with over 220k on the clock. It's a six cylinder GT. The problem is when I am driving the temp gauge will rise usually when I have been driving hard and then waiting at a light. It seems to happen pretty often. Then as I accelerate it will tend to go back to normal. The temp will rise pretty high sometimes..almost to the redline and then very quickly cool down. I recently had the system flushed and filled. This helped briefly but it seems to be acting up again.

Is this a bad pump? Thermostat? Is there an easy check/fix for this? Thanks

6r8ph1X · Post by **6r8ph1X** » Wed Aug 29, 2007 2:59 pm

Mine used to do this when I did a bad job on my flush and fill. It is probably working out air bubbles, thats my guess. What i did was I kept running it and then releasing the pressure from my coolant fill up. Thats where the air bubbles would go. I hope this helps a little. Its my best guess.

Money pit Beretta · Post by **Money pit Beretta** » Wed Aug 29, 2007 10:52 pm

It sounds like the stat may be sticking. If you are going to put a new pump in don't forget to put water pump lube in( I didn't in my 90 and had to put a 2nd pump on). Check also your radiator tanks for cracks, the stock ones are known to split on the seam.

rweatherford · Post by **rweatherford** » Thu Aug 30, 2007 8:32 am

Are you running the AC? If not then it just may take the fan a while to come on. You need to make sure that the fan is operating properly.

Money pit Beretta · Post by **Money pit Beretta** » Thu Sep 13, 2007 8:28 pm

Did you get it fixed?

Mr. Beefy · Post by **Mr. Beefy** » Thu Sep 13, 2007 9:06 pm

Your fan comes on at 223* (about 3/4). A 180* thermostat wil help you out a lot. You would probibly benifit from a radiator flush and make sure you "burp" the system to make sure there is no air in it.

kjlee2112 · Post by **kjlee2112** » Sat Oct 13, 2007 8:37 am

I don't know much about the innards of an engine, but I took mine to get the thermostat fixed and found out something way worse was wrong. The gasket on the manifold was bad and the manifold was cracked at that location. The coolant is leaking and mixing with the oil... making a sludge... possibly overheating my car. My temp gauge goes up to 3/4 and back down to under 1/4.. like a see-saw... the whole time I drive when it gets to temp.. its sad.. but I'm going car shoppin today.. she's been good to me for 8 years.

1988GTU · Post by **1988GTU** » Sat Oct 13, 2007 11:38 am

Just fix it with a new set of updated GM LIMG and lower intake. Unless the engine is rod knocking or locked up, it's worth the updated gaskets. You'll spend 2 grand looking for another headache while you have one already in your name sitting in your driveway. Also, if you stick with GM & is fwd for your next "new" car, it'll most likely be the same engine again. 3100 & 3400 are basically the same designed engine. Fix it.

Connect with your social network account