Hello All
I have checked out many sites for information on this and frankly have not found a good answer
I have a 1989 Mazda 323 non turbo. Engine revs very high at cold temps, at very cold temps it revs to the point that the the high rev limit kicks in, then revs again..... as it warms idle drops, but even when warm seems idle is still a little high.
Thanks
Keith

 

It probably has a slight vacuum leak. Use flammable brake parts cleaner to locate vacuum leaks. Spray it around the intake/injectors/etc. If the idle changes you found a leak. It sounds like the Idle Air Control Valve is working. I would remove the throttle body,remove the IAC valve and clean both. Replace both gaskets and clean the coolant ports out too.