Is this a radiator cap issue?

[graphikg]

My car has been acting wierd lately as far as the cooling system goes. It used to leak from a spot and I never located where. The thing that is confusing is that it is not leaking from that spot anymore. It used to leak until the reservoir was empty whether the car was on or off. Now it doesnt leak, but rather when the car warms up, it will bubble water out of the overflow tube and splurge out some more when the car is turned off.

Sometimes it acts normal but recently cold air was coming out when driving the car and the car was heating up a little more than half. I shut the car off and heard a boiling bubbling sound from inside the expansion tank and/or radiator.

Water pump and tstat are new, so I bought a new radiator cap and car was running cooler as well as hot air was starting to come out of the vents. Is all I needed a cap?

[ethree]

Might be a HG issue, was the coolant nice and clean? How's your oil and exhaust?

[Julien]

you could always give it a good bleed if you haven't already. Other than that if your overflow tank is still overpressurized I'd be worried about head/gasket issues.

and yes a old clapped out radiator/expansion tank cap can cause problems

[graphikg]

The coolant has no oil. I didnt check the exhaust. I hope its not an HG issue since the car has only 12k on the rebuild.

As far as the bleeding goes... its a 24v motor in an 88 e30, so no bleeder screw.