I have a 1990 toyota pickup that i bought within the last year. When i start it and begin to drive within the first mile the temperature spikes almost all the way into the red. Then i turn the key off for a second and start it back up and usually (95% of the time) the temp guage goes right back down to where it should be. I replaced the thermostat and water pump this week and my mechanic says the head is fine.. Could this just be electrical?

 

Mine did the same thing but i have a 97 4Runner and i did the samethings as you and then replaced all my fluids...

 

your temp gauge sender may be spazin out, or you need to burp your system, do a search on radiator burp.

 

OKay, so my check emissions light just came on also. That couldnt be related right?

 

sounds like the thermostat

 

I literally replaced the thermostat today.

 

What engine do you have, is it a 22r?? If so read this:

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

 

Its the 22-re