High idle

[Venom]

01 Chevy Tahoe has k&n intake and flowmaster exhaust with 146k miles. I also run 93. After the truck is warmed up it will idle high after driving it and then putting it into park it normally idles at 600 when warm but now it will be close to 1000 or sometimes a little higher. But once I shut the truck off and turn it back on, it idles fine. And it doesn’t do it all the time. Any thoughts?

 

[Rocket Man]

Clean the MAF and throttle body, see if it still does it. Any DTC’s ?

 

[Doubeleive]

what mark said and check that intake for leaking/sucking in any unmetered air.

 

[Venom]

I’ll do that. And i think dtc means codes? But I don’t have any codes at the moment. If I may add i think it only started doing it since Ive sitting in traffic everyday.

 

[swathdiver]

01 Chevy Tahoe has k&n intake and flowmaster exhaust with 146k miles. I also run 93. After the truck is warmed up it will idle high after driving it and then putting it into park it normally idles at 600 when warm but now it will be close to 1000 or sometimes a little higher. But once I shut the truck off and turn it back on, it idles fine. And it doesn’t do it all the time. Any thoughts?

Don't know if those have one or not, IAC motor and check MAP and MAF sensors too.

 

[Doubeleive]

Don't know if those have one or not, IAC motor and check MAP and MAF sensors too.

01 should have a iac my 00 did and 01 was identical parts wise, for Mike the IAC is the idle air control, it's mounted on the drivers side of the throttle body with 2 screws it's a small valve control with a ball tip on it, usually they get caked up with black carbon grime just like the inside of the throttle body, you can take it out and clean it up real good and clean the inside of the throttle body where it mounts up. usually they cause a low idle condition or make the truck unable to maintain idle at all and just die at a stop sign, etc but I suppose it could have the opposite effect as well.

 

[Tonyrodz]

01 should have a iac my 00 did and 01 was identical parts wise, for Mike the IAC is the idle air control, it's mounted on the drivers side of the throttle body with 2 screws it's a small valve control with a ball tip on it, usually they get caked up with black carbon grime just like the inside of the throttle body, you can take it out and clean it up real good and clean the inside of the throttle body where it mounts up. usually they cause a low idle condition or make the truck unable to maintain idle at all and just die at a stop sign, etc but I suppose it could have the opposite effect as well.

Iac on my Express van went bad and idled at 2200, then 2700. I bought one off Amazon, since not one is even listed locally, and the only way of getting an iac for my application is buying a complete tb assembly from the dealer. The one I got must be wrong because the idle is too low, but I'd rather deal with that then too high. Runs fine after it warms up.

 

[Rocket Man]

Iac on my Express van went bad and idled at 2200, then 2700. I bought one off Amazon, since not one is even listed locally, and the only way of getting an iac for my application is buying a complete tb assembly from the dealer. The one I got must be wrong because the idle is too low, but I'd rather deal with that then too high. Runs fine after it warms up.

What’s it idle at when it’s too low?

 

[Doubeleive]

Iac on my Express van went bad and idled at 2200, then 2700. I bought one off Amazon, since not one is even listed locally, and the only way of getting an iac for my application is buying a complete tb assembly from the dealer. The one I got must be wrong because the idle is too low, but I'd rather deal with that then too high. Runs fine after it warms up.

mine had went bad in my 00 that's when I discovered the aftermarket ones don't work, it has to be a exact oem replacement, I ended getting a oem one from a junkyard and it worked fine.
there are what seems to be hundreds of different ones out there if you look online it's like a endless sea of IAC's lol

 

[Doubeleive]

What’s it idle at when it’s too low?

when mine went bad it would sit there and bounce up and down maybe 350-550 rpm