CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Saturn aura 07 gets to hot overheats sometimes

Hello and thanks in advance for any help. My Saturn aura is the 3.5 and it the tempature started to fluctuate when I drive from a little above half way then will rise to 3/4 and sometimes it will go back down to normal where it’s a little below half way.

I replaced the thermostat then the water pump which the water pump was out … yesterday I replaced the radiator because it had a crack in it. As of right now the car is not leaking coolant but the same issue is still occuring .

I have pressure in the system now I noticed it when I cracked the cap open to hear any hissing sounds … I already bled the system and flushed out the block but now I’m stuck … Oh and also when the car gets to hot and I release a little pressure the resavoir will go down a little .

Thanks for any help .

This could be a blown head gasket letting the engine pump exhaust gasses into your coolant. But first, make sure there’s no air trapped in there from your work: with the rad cap off start the engine and let it warm up. Add coolant as needed. Collect any spillover and dispose of properly. Once fully warmed up, fill the reservoir as needed then cap the rad and turn off the engine. Check rad and reservoir in the morning.

The oil looks normal but I’ll do that before I go to bed tonight… I already drove on it today and it does then doesn’t fluctuate on some drives … I also replaced the radiator cap this morning.