Everytime I drive on the freeway for about 30 minutes, my overflow tank starts to overheat, bubble, and overflow. My radiator doesn't overheat though and my cluster never shows up that my car is overheating. My hose are fine and thermostat was changed months ago. Any idea why this is happening?

 

hmmm you might have air in your system. You are using rad fluid right?

 

Coolant, yes. I've heard stuff from maybe I need a new radiator cap Because Its so old and the seal is gone to... Maybe my headgasket is blown again. But I replaced everything last summer and everything was a-ok and it doesn't have usual blown headgasket symptoms. But my car is revving up sllooooow.

 

I would flush the whole system and get a new cap. If you blew your head gasket you would start to get oil in your radiator.

 

check the oil for coolant first, is it boiling over into the overflow? that does sound like a headgasket especially with the sluggish rev.. did you have the head surfaced at a machine shop when you replaced the headgasket last summer?

 

X2 I would check for oil before the flush.

 

if your dipstick looks milky or it looks like a puddle in walmart parking lot inside your radiator then your in trouble

 

No I didn't get it resurfaced, but after it was fixed, it held up since....' no the radiator is not overflowing to the overflow tank. It's boiling it's on water etc. The dipstick, oil etc... Is not milky. The exhaust is not blowing out smoke. My cluster is not showing up as it's overheating. Yes, my car has been revving slow. And my vtec solenoid has been leaking.

 

hmmm... you got me there.. try the radiator cap, bleed the system, and pray like hell.