Hope someone could help with this low idle issues I've been having, with my 99 Gs400.

Cleaned Throttle body,maf and changed air filter and checked for vacuum leaks.
I'm out of ideas, right now gotta turn rear defrost or Ac to keep rpms up.
Any suggestions are appreciated.

 

Hey bud, did you end up fixing this problem? If not, check that your stepper motor idle control is working

 

how do you check that?

 

Sorry bud, I'm thinking of the old 1uz-fe's. They dont actually have stepper motors now on the newer ones. They use the electronic throttle for the idle. So you would have to check that its working.
Also do a self diagnostic check for any possible codes.

 

ok i'll try that, also gonna have my alternator checked. did a multimeter test this morning (@ idle - 13.8 but with load rpm volts is 12.5)
Think the alternator is going out gonna check it at autozone and check back.
Kinda weird this is my 2nd one Power Steering fluid is not even leaking.

 

No codes, idle still low. Have to be running the ac to keep up the rpm's

 

looks like your oil control valve, OCV, might be shot. Search it's been discussed many times here.

 

Does it happen when its cold also? What exactly is the rpm when cold and then warm?

 

Turn your headlights to the first on position and watch the idle rpm raise a hair...

 

Its about 400 in drive when cold when it warms up its about 200
Bout to just bite the bullet and take it to the stealership.

In the meantime I just run the rear defroster..

 

Did you check your TPS? Didnt you put a new TB on it?

 

Bought one from sewell arrived in the mail today.
Gonna give it a shot and see what happens.

 

ok, before you switch it out try adjusting the one thats there. Just a few taps on the two screws with a long Philips head to break them loose and then loosen. While the car is on and idling already warmed up, slightly move it, see if it improves.

 

ok i'll try that. thanks