Cooling System Problem.

[pontiacdohc@gmail.com]

Hello everyone,Im having some weird overheating problems way random and crazy. Started about two weeks ago I havent been driving the car due to the fact that im not sopsot to be driving cuz a suspened license right now. But about two weeks ago I was driving around all day in like a foot of snow. I shut the car off to go get something to eat and when i started it after i took of like normal and then i nocited i didnt have ne heat i ddint think ne thing of it so I just figured the thermostat went bad after driving it for like five mins the heat heat came back and the temp went down it conituded to do that the rest of the day. the next day i started the car and let run and was ready to leave and the temp was like 220 and no heat so i shut it off and havent driven it intll yesterday I put a new thermostat and rad cap in it i also pulled the water pump off all the fins were still there and there were no sighns of anything being borken so i put a new gasket on and refilled the system. now it has times where it has heat and times when it doesnt all and all it takes allot of high RPMS and driving it realllly hard to get the temp to go down and the heat to work i dont under stand it I let it run for an hour at idel it was fine it had heat and the temp was always at normal it would go up to 220 and the fan would come on and it would go down. i tought it might have been air or somthing intill right now i went out side about an 30 mins and let it run and it just overheated and had no heat at all and the temp was past 220 so i just shut it off!

[1988GTU]

Blocked heater core or radiator maybe. Worse case is headgasket. Do a compression check.

[Carlspike]

Make sure you bled it correctly with both bleeders, some people have problems with air bubbles getting stuck. Where did you get the new thermostat? I've had horrible luck with aftermarket t-stats in the past.

[pontiacdohc@gmail.com]

i went and got another t-stat becasue i took the old one out and ran it without one and the car didnt over heat and I had heat it awhile to get heat but I had it , so I went and got another t-stat like i said and I put it in and let the engine run for about 30 mins and it was fine i had heat and the temp was normal. WELL TONIGHT I got outside and start the car because I haven't driven it since the wed I dont reallly drive the car that much anymore because my license is susspened right now and all the cops where i live know it is and what car I drive so I have been driving my girlfreinds sunfire. anyways I dont understand why the car would be fine without the t stat and then i put a brand new one in that i tested befor i put it inm and it work one day and not the next.. i do live in mich and its like 20 degrees out also THIS MAKES NO SENSE TO ME ALL!

[dohcfiend]

sounds like a blown headgasket. check your coolant and oil for cross contamination and proper levels.

just a couple obvious things but you do have enough water in it and you did bleed it right?

[pontiacdohc@gmail.com]

the oil looks fine and the engine isn't smoking as far as a compression check goes i don't even want to think of how im going to run a compression check the back cylinders of this engine!

i took the t-sat out and i have been driving it very only on emergences ive been very busy with another car lately so I haven't really giving this allot of attention
Its fine without the t-stat in it the heats works, it doesnt get super hot but it works and the car doest overheat at all. I was thinking maybe a kinked hose or somthing there is a hose that runs of the water pump that runs algon the passensger side of the car that goes into the heater core i think that is pretty much kined all the way down do to the fact the it was a steal line that stareted to leak and i just replaced it with rubber hose maybe it isnt getting enough pressure to push the t-stat open i dont know but its reallly starting to piss me off , and if it is the head gasket i think this car will be sent on its way to the junk yard