Hello everyone. The issue that originally haunted me was a slight surge of the idle after having reached operating temperature. I decided to clean the throttle body to see if ...

Hello everyone. The issue that originally haunted me was a slight surge of the idle after having reached operating temperature. I decided to clean the throttle body to see if this would possibly go away.

I removed my throttle body yesterday to give it a good cleaning with Valvoline Heavy Duty Carb & Throttle Body cleaner. I realized the 2003 doesn't have a throttle cable which is NEWS to me. I could not get the sensor on the side off so I made do and cleaned it semi-dismounted. I op-tested as soon as it was all put back together and the problem was still there. I decided to give up, maybe the truck just has a rough idle because everything feels fine when I'm driving around.

I thought I did a good job of cleaning it, but evidently I did not. Last night, as I slowly idled through my parking lot I noticed the throttle would stick. I did it a few times just to be sure it wasn't sporadic. I rev'd up to around 1300 to slowly drive and I had to hit break in order for the TAC to drop back down to 600 RPMs or "IDLE".

May need to do a relearn. If you drive it a hundred miles, it should reset itself and be back to normal.

Is this "re-learn" a myth or fact?

I've heard there are bearings inside the TB that are for the little butterfly. I may have cleaned this too well and rubbed the grease off.

Any truth to this?

As long as you didn't soak the electrical parts with cleaner, the TB should be fine. If the relearn doesn't work and it does not adjust itself, you may need to have the truck reflashed by a dealer.

Your TB adjusted over time getting used to the carbon build up. When you cleaned it, you removed it and gave the butterfly more motion. Computer is now confused and doesn't know proper idle or driving rpm.

This seems more feasible as compared to what another forum recommended about the bearings grease being removed by my cleaning.

So then it is fact that the ECU needs to relearn the idle? I ask twice because I think it's marvelous and ingenious.

Yup, needs to relearn.

Interesting. I will give this a try. Thanks dude.

Since I am home now I have a little more information for you. Looked at repair manual and the relearn procedure is as follows:

2003 Silverado / Sierra idle relearn procedure :
Disconnect your battery for 30 min.
Reconnect the battery
Start truck and allow Engine to get to normal operating temperature
Block all 4 wheels
Start and put it in Drive for 5 minutes
Put the truck in Park for 5 minutes
Turn the truck Off.


Good Luck, hope it works for you.

Now I need to find 4 blocks! I will try this tomorrow!

The manual state this is to be done after TB cleaning?

BlackZ71Silverado wrote:Since I am home now I have a little more information for you. Looked at repair manual and the relearn procedure is as follows:

2003 Silverado / Sierra idle relearn procedure :
Disconnect your battery for 30 min.
Reconnect the battery
Start truck and allow Engine to get to normal operating temperature
Block all 4 wheels
Start and put it in Drive for 5 minutes
Put the truck in Park for 5 minutes
Turn the truck Off.


Good Luck, hope it works for you.

I did this today. The only thing I didn't do was block all 4 tires. I just leaned the truck on the curb and I figured that would pretty much simulate what they wanted because it wouldn't move forward while in DRIVE.

The truck still sticks at around 10-15 mph and will not slow down unless I press the brake...