So I recently installed a new factory toyota thermostat in my 4runner, since the previous one was continuing to stick open, but now everytime I leave my house in the morning to go to work itll run about 3/4s of the the temp gauge before opening. After that, it runs normal the rest of the day. Doesnt overheat while wheeling or anything, just first thing in the morning. There is plenty of coolant, and Im not leaking anwhere, or atleast that I can see. Any advice? Anything would help at this point. THanks!

 

another bad t-stat?

they're made cheaply, and I've had more expensive parts come factory defected.

you can run the t-stats from an autopart store, they go bad every 4-5 years IME.

 

See:
- http://www.4crawler.com/4x4/CheapTri...tml#Thermostat

 

but isnt it strange how it only does it that one time? and then doesnt do it again till the next morning? I just thought that was the strange part...

 

Yes, that is the classic symptom of the 22RE Temperature Overshoot problem. Only does it at first warmup. Read the full text of the TSB on the web page I linked to above.