Bad thermostat or air?

[ExoticKiss]

I'm back again lol

1989 Toyota Camry LE V6
I just had the radiator changed over the weekend. Ran fine on the way back, heat worked great.

This morning I went to leave for work. Had the car running for a good 10 minutes before I left. It was blowing great heat, the temp gauge was a little under the half mark, where it usually runs.

Go to leave and not even half a mile down the road, I pretty much lose all heat and the temp gauge drops to a little below C. It's about 35 miles to work, which I spent freezing. By the time I got there the gauge was still only a very little above the C. I get into a parking spot, through it in park and the temp gauge goes up to a little under half and it's blowing great heat again.

Did the same thing when I left for lunch and when I left to come home. It was a little better on the way home though.

We opened up the radiator cap and a little air came out. We tried bleeding it but no air came out. Yet it's still dropping quite a bit just after driving 1/2 mile - 1 mile.

Could it be air in the system or could it be the thermostat? Or could it be something completely different?

[91 2VZ]

Either the thermostat is stuck open or air is in the system is my guess.

[white90dx]

Its probably the thermostat... It should be a quick fix to replace it. Get the Toyota OEM one if you can - its should fail open just like your current one (instead of closed, like my last one!).

-Charlie

[DM89]

this happened to me just before a five hour drive in winter. Changed the thermostat and its been fine for two years.

[jaduncan]

Till you can get to it... slide a piece of cardboard in front of the radiator, cover how much it takes to get heat while driving without overheating while idling.