Overheating problem

[JSteiner]

Okay, i've got a dillemma:

95 Grand Am
3100


Just replaced LIM gasket, T-Stat, Coolant temp. switch, and thoroughly cleaned both intakes. I'm still overheating. I've been trying to bleed this for the last week and a half, and i'm not getting any more air out. My temp will go just to redline if i'm idling after driving a while. If i hit the gas, my temperature goes down. Cooling fan is working properly. Any ideas? Anybody run into this before? At first i thought it was just a tough air bubble, but it's not getting any better. Please Help

[doobiess]

Ok well saying the fan works... ok i assume it works when you turn AC on.. does it come on basically shortly after the halfway mark? Does is smell like gas out the tailpipe? do you have engine lights on the dash? ok well as for mine i have a 94 3100 and my temp will climb pretty fast up until the fan kicks in at the 2/3 mark or so maybe less and the fan is able to maintain the temp and slightly drop it... but as for yours dropping as soon as you hit your gas... could be a sign of a sticky thermostat... mine was... and assuming not.. and also it could be possible your temp sender could be faulty... because it might not be that actual temp... also is your rad cap holding pressure. I assume your serp. belt is ok.. and not slipping at all... if it were you would hear it ...

[Silver99SE]

Does it have an electric water pump? Because it seems that when you hit the gas it is cycling water through the system faster. It could be that your water pump is going bad and only pumps fast enough when the RPM's are up. I'm no mechanic but it could be a possibility.

[JSteiner]

i appreciate the replies. I just replaced the temp sender, and i'd be hesitant to suspect that. After talking to the master tech at my shop (i'm just a service writer, i don't have to know anything. lol) he was making me lean toward the t-stat as well. I tested mine in boiling water before installing, and it seemed okay, but you never know. Could be opening up at too high a temperature. My fan kicks in properly, when the AC is on, or when i hit 220. The belt is fine and not slipping. The water pump is mechanical and belt driven. I don't smell any gas in the exhaust, and the check engine light does not come on anymore. (it used to until i cleaned my EGR port on the upper plenum)

I'm thinking about replacing the thermostat and see where that gets me

[doobiess]

ok well as for the thermo... at the bottom of it.. if you press up on the spring... when i removed my old one it was sticking... and well i placed the new one in... obviously didnt... but as for temp ... mine climbs alot too.. and i do say i dont care for it at all... im about to replace an o2 sensor.. and i assume it wont do anything for temp... but i was also considering a bigger tranny cooler... wondering if that would effect overall temp of the engine...

Also you could do a complete rad flush.. and since i cant tell if its all built up since we both fill it by the resivior.. i might just remove the whole rad.. and do a big flush... and for your case check to see if any of the fins on the rad. are bent... if so.. try and straighten em out that will help but if you have like 1 or 2 dont worry about it...

[JSteiner]

I replaced the t-stat today. No dice. Still doing the exact same thing... I'm gonna get the system flushed tomorrow and see what happens. I'll let you all know.