[Deshi]

I was revving high and was on my way home when I took it to about 7K. I noticed the temp guage would DROP to 1/4 on it instea of being 1/2 like normal. It would then rise back to normal temp when i shifted. any ideas?

 

[ITA-MR2]

Possibly a bad thermostat; or possibly air in the system.

 

[mental105]

what was the outside ambient temp when it happened? it could be the outside ambient temp. and vehicle speed. when your engine is spinning that fast the coolant is circulating really fast causing a drastic drop in engine temp.

 

[Deshi]

do I have to bleed the coolant if I replace the thermostat?

 

[jimi]

I had the same problem, fitted new thermostat, bled the system and all ok after that
hth
Jimi