High idle

[gsyk59]

Ok, looking for some help and direction. I've got a 2001 that has been running fine. Just recently it's began to idle much higher. Used to be around 900 now it's up to 1500. Thoughts?

[black roadster]

Try seafoam first. One in the fuel tank and suck one into a vacuum line on the intake.

[Rogue]

Techron Concentrate....No Fire trucks called and no Reckless Operation tickets.

http://youtu.be/utW2IQbkMNo

[POS Racing]

Another question is what did you do to the car just before it picked up the high idle??

[gsyk59]

I didn't do anything to the car before it started idling fast. It's been setup the same for quite a while with no problems.

[POS Racing]

I'd go the techron route then.

[gabkwong]

Also, clean the butterfly and housing of the intake manifold. Don't use abrasive solvent. Some threads say it may damage the surface coating.

[EricJ]

i.e. since it is a Throttle Body, use a Throttle Body Cleaner.
I'd also check for any loose vacuum hoses, since it started 'all of a sudden'.
On my '99 when I did the manifold clean, I also cleaned the Idle Air Control and the EGR valve. '99's have a bigger problem with dirty manifolds. But an '01 is still 12 years old.
See: http://www.miata.net/garage/manifold/index.html

[SirHustlerEsq]

Follow Eric's directions, then start unplugging stuff to see what does and doesn't change the idle.

[gsyk59]

Ended up needing a new idle air control valve - ouch. Thanks for the suggestions and help though.