Issues with idle relearn after cleaning throttle body?

[notspartacus]

My 07 Tahoe gave me a P0121 code and I took out the throttle body and cleaned up all the nasty gunk in there and put it back on. I followed the basic idle relearn which was idle for 3 min, off for 1, idle for 3 min and off for 1. I even went on and off the highway a couple times to get it up to 50mph+

The issues I'm seeing right now is when I'm coasting at very low speeds in a parking lot at around 5mph the RPM will automatically rise to 1k and increase speeds to 10-11mph by itself without my foot on the gas at all. Is this just the engine still in the process of relearning the idle or something a bit more serious?

 

[OR VietVet]

Sounds like it. AS this article says, do it all again.

1) Start the engine and let it idle in park for 3 minutes. During that period the idle may be higher idle than normal.
2) After 3 minutes, turn the engine off and leave it off for 60- seconds.
3) Start the engine again and let it idle in park for 3 minutes one more time. During these run periods you may see a check engine light. Scan for codes and if you get throttle body related codes, clear them.
4) If the idle speed is still off, drive the vehicle at speeds above 44-mph and operate several acceleration and deceleration cycles. Then repeat step #3 one last time.

 

[notspartacus]

Seems like the issue was also tied to the MAP sensor, after replacing it the idling and RPM is now normal.

 

[Jetav8r7]

i've cleaned my throttle body numerous times. and this happens every SINGLE TIme..... I've followed the GM recommended re-learn procedure. it doesn't work on mine. I just limp it down the road to a shop and they relearn it for $50 takes them about 5 mins. that included them checking me in. after dealing with this. i just don't screw with until its absolutely necessary. I have over 460,000 miles on my 2010 tahoe. I better get another million out this vehicle.

 

[swathdiver]

i've cleaned my throttle body numerous times. and this happens every SINGLE TIme..... I've followed the GM recommended re-learn procedure. it doesn't work on mine. I just limp it down the road to a shop and they relearn it for $50 takes them about 5 mins. that included them checking me in. after dealing with this. i just don't screw with until its absolutely necessary. I have over 460,000 miles on my 2010 tahoe. I better get another million out this vehicle.

460K miles? Goodness, you gotta do a write up on this truck and tell us how/when you've maintained and repaired it.

 

[OR VietVet]

What got me was when he said he better get another million miles out of it. To me, that means, he already got 1 million out of it. But I know he means he wants to hit 1,460,000 miles.Either way that mileage is impressive. The other thing must be that there is likely hardly any rust on that rig.

 

[Jetav8r7]

I have replaced the rotors 2 times. throttle body. plugs and wires of course. 2 driver side motor mounts. I just replaced the serpentine belt. The compressor belt is still original. It may squeak every now and then.and The tranny was replaced the last July. I did the oil changes mostly myself. but however. I'v let Walmart start changing the oil. Because cause it cheap and i just don't feel like doing it. I'm am not seeing any oil burn between changes like others have seen. This Tahoe can run gasoline or CNG. which we us CNG primarily. The oil change intervals running on CNG 10-15k. and the oil would not be showing dirty. Years later I change to every 3k. And the Chevy DOD tick has gone away.I've replace the ac blower motor. And a steering wheel position sensor. The tranny cooler line from the tranny to radiator has been replaced, and I notice last week that the tranny cooler line from the radiator is starting to weep. So thats got to come out.

The left drivers side of the radiator tanks has also starter to weep antifreeze. The main seals are all still good. No oil on the underneath side of the motor or tranny.

I would say the single most frustrating thing I've dealt with on this vehicle. is the DAMN grounding issue. which cause a host of symptoms that everyone is familiar with. My Chevy dealer spent 16 hours of DIAG time. Call and said we can't find out whats wrong. But they didn't charge me a dime. Thank GOD for the internet.

 

[89Suburban]

i've cleaned my throttle body numerous times. and this happens every SINGLE TIme..... I've followed the GM recommended re-learn procedure. it doesn't work on mine. I just limp it down the road to a shop and they relearn it for $50 takes them about 5 mins. that included them checking me in.

Same way mine went, except I let Pep Boys **** me for 80 bucks to do it.

Hey 460K? Damn, some inspiration. I am ready to hit 320K on mine.

 

[Jetav8r7]

Same way mine went, except I let Pep Boys **** me for 80 bucks to do it.

Hey 460K? Damn, some inspiration. I am ready to hit 320K on mine.

I pay 19.99 I think. I don’t do all that synthetic stuff ,high dollar motor oil. I just keep it changed. I read somewhere ,you change your oil frequently the seals won’t leak...seems proven true so far.And we’re not just run around town with this Tahoe . We’re towing with it.And a lot of the tows are at max gross.But I’m also not rapping this motor out getting on the freeway during a tow.

 

[89Suburban]

I pay 19.99 I think. I don’t do all that synthetic stuff ,high dollar motor oil. I just keep it changed. I read somewhere ,you change your oil frequently the seals won’t leak...seems proven true so far.And we’re not just run around town with this Tahoe . We’re towing with it.And a lot of the tows are at max gross.But I’m also not rapping this motor out getting on the freeway during a tow.

No I meant I had to pay $80 for them to relearn the idle for me with their computer.