I had a problem with my radiator where it was leakin coolant. It overheated twice while my radiator was messed up. But I replaced the radiator with a new one and it worked fine, but last night when it rained I turned on the A/C and after a while I noticed it started overheating again. What could it be? Is the head warped and is this why its overheating?

 

Could be a head gasket. Could also be that your A/C is overcharged. I have seen both of those cause overheating. If you start to overheat and you turn on the heater and it doesn't get cold, you have a blown head gasket.

 

I'd also like to add that it could be your thermostat...fairly cheap and easy to replace so you might want to give it a shot first.

 

try thermostat

 

It's most likely the thermostat -- should be ~$9 at a local parts store.

 

Check the water Pump. They are made to leak when they wear out. Check where its leaking from. Is it all splattered on the underside of the hood above the Belts? If so...Water Pump.

 

did u ever replace the radiator hoses? my car was leaking coolant slowly after swapping in a new radiator...i got new hoses and everything is now fine.

 

I already replaced the thermostat and no I haven changed the hoses.