Here's the deal. My temperature gauge goes up to H, back to normal, up again, and back down. I'm really pulling that it's a temperature sensor, but I really don't know. I took it to my mechanic who 'supposedly' did a pressure test on it and told me to buy some K- Seal and that it was my head gasket, since I didn't have the $1200 to dish out for a repair. After pouring in that stuff to my radiator, it still fluctuates and I'm thinking there's no easy way out of curing a blown head gasket. Any ideas?

 

Flush that nasty stuff out the cooling system and then bleed it.