Code:P0121 gunked TB?

[rosendo192000]

That's right I've just had a CEL come on my 4.8 Tahoe .Everything seems ok ,idles fine . I think it's more Likely to be my throttle body asking for a cleaning . Now I've done my search but have couple question before make any thing worst ,
1. Any specific cleaner brand I sure use or stay away?
2.Is it as simple as removing the intake tube attached to the TB and spraying into the butterfly? And wiping it clean ?Tips or suggestions
3.Anything else I should clean or be careful with ? MAF? Same cleaner ?
4. Now after doing my research , most likely I will need to have it relearned , or can I really get it to adjust by having a 200-300mi trip? Or would I have to take in to GM .? If I end up going to GM what should I ask for?

Thanks

07 Ls
Stock with K&N Filter
104xxx

 

[KMeloney]

Rosendo -- I'd be surprised if your TB really needed cleaning.

I went here:

http://www.obd-codes.com/p0121

...and didn't see anything about needing to clean the TB.

Hopefully it IS something as simple as that, but I doubt it. It was recommended to me that I clean my TB when I was getting a rough idle. It looked pretty darn clean, and it didn't do anything helpful at all.

 

[07whitetahoe]

Usually that code will come up if the TB won't reset back to factory calibration. Like when the battery has been disconnected, or if i's really dirty, during normal driving and has never been cleaned but won't go back to "0".

You can just take it off. I generally take them off, get a can of carb cleaner and a small brass wire brush (brass won't scratch the aluminum, steel can) or fine steel wool. Take out the sensors, and clean.

Bolt everything back up, if you have a scan tool, clear codes. Reset PCM- pull battery cable, wait about 15 minutes for residual power to subside. Hook back up, turn key on and allow computer to get it's baseline. Start and let run. The computer will be in a re-learn mode so it may run funny for a bit.

On a side note- you may be able to pull the PCM fuses instead of battery cables to reset the PCM. If the battery cables are removed, a reset of HVAC may be needed which is a whole other thing. I would try that first before removing battery cables. Either way, the computer will need to be reset for the TB to return to factory "NEW" setting.

*I just read you have a K&N filter. Those are notorious for ruining electronics on upper manifolds. Especially after cleaning and over oiling. This may be something to look into as well.

 

[rosendo192000]

Thanks Kmeloney & 07whitetahoe , it seemed to the just a dirty thottlebody . I cleaned it this morning cleared my codes and no CEL yet . It use to come on when I drove them idled for a bit . I'll post any other news within the week . Thanks again

 

[rosendo192000]

Yup it's official , no more codes. The truck has been relearn by its self within a 75 mile drive ( no constant ) . And to top it off it response better then ever .

 

[07whitetahoe]

Great!