Common Skyline Problem!

[shyr33]

Gdays it looks like the common cold idle problem has hit my car(94 R33GTST). As i start her up in the morning the idle either rises to about 1500-2000rpm straight away or as soon as i start driving and stop at some lights. This occurs until operating temperature is reached where it goes back to normal.

Now i have done some research before i ask this question and am just a little confused on something. Is it this cold start valve causing my problems (which i assume controls idle when cold) or the AAC valve (which i thought controlled idle along with the ecu/IAC valve when normal operating conditions are reached).As you can see im a little confused. Due to being a busy uni student i dont have much time pulling of everything and giving it a clean so i only want to go after what i/people think is the main problem.

Any help would be appreciated

Thanks

[DRD-00F]

problem?

so what your saying is, when the car is cold, it ups the revs to warm it up... then when its warm, it stops doing it?

where the hell is the problem there?

[FLY-4DR]

u will find most cars will do that

mine will sit around 13 then down to 800 once warm

[cliff25gtst]

same here mine sits around 1200 - 1300 and then once warned up will drop to 800.

no problem with that?

[jimmytim]

err...it is normal...to prevent the engine from stalling when cold...

[shyr33]

Sorry should of been a little clearer, i mean once i start it, it will sometimes idle at its normal cold start value what your talking about but then i take it out of the driveway and drive it around for a little bit and then i stop at some lights and poah it shoots up to about 2000rpm while im sitting there and doesnt go down. Its like a valve forgets to close/open or something thats my problem and why im asking.

Thanks for the quick replies so far guys

[shyr33]

bump any ideas guys?

[SilverECR33]

its still warming up, isnt it. You need to give it about 4 minutes to warm up before you set off. at least, try that next time, and see if it still does it.

[mrgilly]

Sounds like your automatic choke dude, although 2K RPM is higher than I'd expect it to sit on

[DRD-00F]

  mrgilly said:

Sounds like your automatic choke dude, although 2K RPM is higher than I'd expect it to sit on

agreed... a bit high... but none the less, it has been really cold lately... it doesnt use much petrol, and its mostly good for the car...

as long as it doesnt do it after like a 30 minute drive then your fine...

[shyr33]

Thanks for the reply guys, well i could leave it for 5 minutes to warm up and then start driving then when i stop instead of idling at normal rpm's it will idle somewhere close to 2000rpm. I know its not a normal thing because i have had the car for like 3 years without this happening before. And it has also occured after like 20 minutes of driving just last night. So im very confused. I know about cleaning the AAC valve and that but is there a separate valve what controls the car at idle when cold or is it just the AAC controlling idle? If people could clear that up for me that would be great thanks.