2007 Escalade with 74k miles, I was getting a check engine light and the code came out to P0121, which is Throttle Position Sensor (TPS). I brought it to a GM dealer today and they checked and said the TPS was fine and found the throttle body had excess carbon buildup and that was causing the TPS to put out the code. Since the TPS was fine, there was no powertrain warranty, so they wanted about $250 to clean the throttle valve and then "Relearn Idle".

I did not have them do it and brought it home and sprayed Gumout throttle body cleaner in it myself and reconnected everything. When started back up the idle in park is about 2,000 RPM so it looks like he was correct with the diagnosis anyway.

So my question, is there a way to do the idle relearn by myself or do I need to bring it back in to the dealer? He mentioned there was 2 different ways to do it, one was a scan tool and the other was punching some kind of info in the driver information center or something like that. I have been searching for hours and did not find anything specifically for the newer Escalades and there are tons of different DIY on other brands.

Oh I also tried disconnecting the battery and driving it for about 10 miles and that didn't fully work, but the idle does go down on it's own sometimes now but as soon as I press the gas pedal it goes back up to 2,000 RPM (in park)

Just an update,... drove it around some more today and it seems like the idle is calming down some. Looks like it is relearning on it's own, which would be nice...

It will relearn on it's own over a few hundred miles. I will look up what the service manual says when I get home

I am told that it will re-learn on its own over time. The "reason" for the dealer performing the re-learn process is because customers would complain about the vehicle not being right when they leave the dealer. Just what I am told....

It will relearn on it's own over a few hundred miles. I will look up what the service manual says when I get home

hcvone & tss, thank you for the reply, you were right, it did learn on it's own, took about 100 miles over a 3 day process. It's back to normal idle and running very very smooth. For those thinking about doing it, it's totally amazing how much difference the cleaning made, it didn't even look like there was that much carbon in it when I cleaned it so i didn't expect much. The motor feels like it's brand new now. The owners manual recommends it at 75k and mine was at 74k...