I have a 93 Mazda 626, 2.0 - 4 cylinder, manual transmission. The engine idle "races" or varies from 800 rpm's to 2000 rpm's whenever the clutch is pressed or the transmission is in the neutral position. This only happens once the engine is warm. I took it to a Mazda Service Department but they were not able to solve the problem. Any ideas?

Thanks

 

Try disconnecting the Throttle Position Sensor when it is surging. TPS is common problem for surging problems especially on older systems. Could have a stuck neutral switch but would not think that would cause idle surge like that bad.

 

Did you ever get a solution to this??? I've got a 91 626 which does a very similar thing when turning steering wheel close to full lock, at low speeds i.e. when trying to park in a tight spot. I'm very puzzled. I looked through 45 pages of this forum and yours is the first similar prioblem.

Cheers, Paul.

 

same thing happens on my 93 mazda 626 2.0L when its cold but when it warms up it usaly stops.... or sometimes just randomly happens...