my temp gauge isnt right somehow......it goes up to where is sposta be after the car is warm, but sometimes it goes back down to zero as the car gets warmer...i think it may be the thermostat, but any idea what could cause this?

 

check the little sender sensor for the temp cauge. Its the little plug before the temp switch

 

Probably just a bad contact on the sensor.

 

How's your heat? If your heat doesn't blow hot when the gauge goes back down, you need a thermostat.