1G cold start very high idle, surge when moving?

[91DSMdave]

Hey, i just started having this problem the other day and i cant find much info on it. If i let my car sit overnight, when i first start it in the morning my idle is wayyy high, like 3k. And to top it off, as soon as i start moving the idle starts surging, but if i come to a stop it will slowly go down to normal. The car only does these things when it is cold and not fully warmed up, once or twice it has surged while moving completely warm. ALSO the car seems a bit sluggish in boost,. and i can feel hesitation. My AFR's are constantly changing, i had them tuned to around 10.5-10.8 at wot, then it went to around 12's, now its lucky to see above 10.2 at wot. I have checked for vac leaks, torn intercooler couplers...nothing. Im stumped, someone please help.

FORGOT to add that on the overnight startups, the afrs are around 11.5 during the high idle problem.

 

[cliffkemp]

Check your BIS screw. Sometimes, they get loose and back off some. As for the a/f ratios, it sounds like it could be your TB seals are going or, depending on your BOV, it may have a seal going bad in it too or not handling the boost you have set anymore.

 

[92AWDHX40]

Check dsm idlesurge lots of info.

 

[300hpbound]

You said that you've checked for vacuum leaks but man does it still sound like a leak somewhere. I had a plug come off my intake pipe a few months ago and it did the exact same thing. Check around the intake pipe, after the maf. Start up the car and spray carb cleaner around any area that could have a leak, couplers, throttle body, vacuum lines even injectors as the o-rings like to dry up. If it revs up, there's a leak there.

iugrad mentioned the idle surge troubleshoot, here's the link:

Terry's Talon Troubleshooting Tips #3 - Fast Idle (aka. Idle Surge)

 

[Dude3000zx]

i had this problem when i bought my eclipse and the problem was the idle control sensor mounted on the throttle body right next to the tps.

 

[jmkoons]

An old FIAV on the throttle body also wrecks havoc on idle control. I could afford to block mine off with California weather, and it was the best stability improvement to my idle and light throttle response in years. Obviously, all the idle surge points are key, and I'd been through that list a few times.