ok here in ohio its cold as fock and i didnt drive my car for 2 days and then i went out to start it up it wouldnt barely start but after i let it run for 15 mins. i went out and the heater wasnt blowing any heat. so i took off down the road and the temp gauge started to go up it went almost all the way up but if i just let it sit there and idle the temp gauge comes back down were it normaly is. so wut do you guys think it is thermostat or head gasket . coolant level is fine. its the first time ive had this problem. any help thanxs

 

thermostat

 

I had this same problem in my ZC I bet your Head gasket is going, my sure you check your coolant often. Rob

 

i think the fel-pro head gasket might be the problem i put one in last winter i was poor and being cheap thats why i used fel-pro junk . But im going to do a block test on it and se wut happens.