[nasty92LX]

Not sure if i have a bad head gasket. The whole topend is about 5 months old. About a week ago when the car is cold and it warms up the temp goes almost up to 270 then goes down to around 160. After that u can beat it and it wont move. So i changed the thermostat to a 180 and now its fine. If you look in the overflow it has bubbles coming out of it but the is no anti freeze in the oil or not smoke comin from the exhaust. The temp stays ice cole now. Just not sure why there is bubbles coming from the overflow.

 

[Mustero]

Check/test your radiator cap or just replace it

 

[nasty92LX]

My rad cap is about 4 months old.

 

[SALIV8]

pressure test your cooling system, or pull our radiator cap while its cold or u willget burned, and start the car. rev the engine and have someone look at the coolant in the radiator and see if the level changes, or bubbles. that is usually a sign of exhaust gas in the coolant

 

[Mustero]

My rad cap is about 4 months old.

4 months old or not if you overheated,it could damage the caps ability to hold pressure.Just a thought. Pressure testing the system & cap is really the best way to find leaks.Leaks not only give coolant a way out but give air a way in

 

[WAR-PARTY]

pressure test your cooling system, or pull our radiator cap while its cold or u willget burned, and start the car. rev the engine and have someone look at the coolant in the radiator and see if the level changes, or bubbles. that is usually a sign of exhaust gas in the coolant

Ya can get a kit at AutoZone or Advanced Auto