ok guys need help tryin to figure this one out.

car symptoms: rough idle like as if were misfiring but its not main thing is overheatin then drops temp then overheats and then drops again and then just stays high

what i've done so far: new aluminum radiatior, water pump, replaced all hoses and radiator cap

my guesses which i havent tried yet but are thinking: radiator fan gone bad, heater core (maybe bypassing it) coolant temp sensor



what do you guys think before i attack the car again when i get it back???

 

make sure the fan actually turns on..... but the problem kinda sounds like a head gasket.

 

^^^^

+1

 

thought of that but i didnt think it would be an issue this soon with only 110k on it and never driven hard only once in a while

 

no smoke either just noticing the coolant res. goin low and having to fill it up every couple of weeks thats why i also didnt think it was a head gasket but it could be.....how could i test that out to confirm its a head gasket????

 

coolant leak down test will tell you. if you dont have the tools to do this, simply checking the plugs will go a long way

 

Check your oil. If it looks like chocolate milk then you have coolant leaking inbetween the coolant and oil passages. The other thing is there may be air in the system still. Did you purge the system before you capped the radiator?

 

purged it angled it bubbled it put the heater as well......last few oil changes didnt notice any milky oil so i kno thers no coolant in the oil

did a pressure test several times and the gauge goes down but i still cant find any leaks anwhere. i was wondering if the heater core is clogged or had a leak would it drain out through the ac drain or build up inside ??? (my carpets arent wet on either side)

 

Headgasket can blow between coolant and combustion hense pressure going down on pressure test. You wont see the leak its internal. What year car are you working with?

 

wha t about the stat ? Does it have one? could be sticking then opening. Simple stuff first