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PO121 code

07AVMAN

Full Member
Joined
Jan 7, 2010
Messages
9
2007, 5.3l, 61k is getting code PO121 and research shows it is the TPS. Is it a replaceable part or do I need the whole throttle body? Did not pass emissions due to this code. Would cleaning the throttle body solve it long enough to pass?
By the way, it runs great no issues of running rough or stalling.
Any help would be greatly appreciated.
 
tps or throttle position sensor is a replaceable part usually not to expensive bolted to the throttle body usually would find an unusual idle or lack of throttle response with a problem there the first thing i would do is unplug it clean and dielectric grease the connection and see if the code goes away
 
Thanks I will give that a try.
I believe it is located directly on top of the throttle body just back from the intake?
Another question...can I clean inside the throttle body with straight carb cleaner or do I need to get special stuff?
Thanks for any help.
 
The throttle position sensor will be located on one side of the throttle body.  The shaft that turns the throttle butterflies will literally turn the TPS sensor.  The sensor itself has a spring-loaded mechanism, which usually requires some preload -- you might have to put the TPS sensor on the throttle body crooked, then rotate it into position to be bolted in place (or else move the throttle blades by hand as you install the sensor).  I've not replaced one on the Avalanche before -- only on older cars - so I cant say for certain.

I prefer using Seafoam to clean the intake tract.  Whatever you use, just make sure it's sensor-safe.  Some say carb cleaners can remove special coatings on throttle body blades aimed at preventing carbon buildup, but I've never looked into whether or not that's true.
 
Thanks,
I did clean the throttle body and now can't get it to relearn the throttle position. I tried the run 3 minutes off 1 mintue and on for 3 minutes to no avail. Then tried driving it for over 20 miles over 45 with decellerations and idling off and on.
Can't figure it out. Any suggestions?
 
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