01 se engine temp problems

i have a 01 grand am with the quad 4 engine, just replaced the radiator after the original was cracked in a car wreck, now when im using the heater and my engine is at idle the temp gage crawls up to about 230 and im only getting cold air out of the vent, then when i accelerate the air gets super hot and the engine cools back down.....thought maybe thermostat but would like to know for sure cuz i hear its a pita to change on the quad 4....any help appreciated!!!

possible air in the cooling system. when doing any work on that system, you want to ensure that there is no air left in the system. it can cause hot spots and the coolant wont move the way it needs to for heat and engine cooling.

:iagree: with air trapped in the system, specificly the heater core.

Try letting it idle with the radiator cap off with your heater on highest heat setting. This can take some time if a lot of air is trapped.
Also as the air gurggles out, you'll want to keep an eye on the resevoir coolant level and make sure it doesnt get to low and suck more air into the system.

Hope that helps!

Thanks for the advice!!! I ran it with the cap off sure enough i got air bubbles out and its runnin at the correct temp now. Thanks Again!