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Getting reduced engine power message, DTC codes are P1516 P2101 and P2176. The car had been somewhat hesitant prior to engine shut down.
GM Tech (Cam) :
Hello, Please include all the details about your issue so I can accurately advise you. I cannot see your vehicle so please detailed information.
This PI was superseded to update model years and add information concerning idle surge, reduced engine power mode, and/or DTCs P0068, P0121, P1516, P2101, P2119, and/or P2176 that may be experienced on high mileage vehicles. Please discard PIP4578.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
As carbon builds up in the throttle body of a high mileage vehicle, the ECM/PCM learns to compensate by increasing the throttle plate angle.
If enough carbon builds up, an idle surge, deceleration surge, tip-in hesitation, reduced engine power mode, and/or DTCs P0068, P0121, P1516, P2101, P2119, and/or P2176 may be experienced on high mileage vehicles.
If the throttle body is cleaned without performing an "idle learn reset/reset idle learn" with the Tech 2, the ECM/PCM may continue to compensate for previous carbon build up, causing it to return with a similar concern as well as DTCs P0121, P0506, and/or P0507.
In a similar fashion, if the ECM/PCM of a high mileage vehicle is replaced and/or reprogrammed without performing the Throttle/Idle Learn outlined in SI, the ECM/PCM may no longer compensate for existing carbon build up in the throttle body, causing it to return with a similar concern as well as DTCs P0121, P0506, and/or P0507.
If SI diagnosis does not isolate the cause of this concern, inspect the throttle body bore and plate for obvious carbon build up.
If carbon is present, follow the Throttle Body Cleaning Procedure in SI to clean the throttle body.
After ensuring that the throttle body bore and plate are clean, perform an "idle learn reset/reset idle learn" with the Tech 2 and re-evaluate the concern.
Reading your info.... The car was hesitant prior to engine shut down. It also had a idle surge then shut down all today. I changed plugs last week, all connections were checked and OK.
Approx 13700 miles on vehicle
Ok, I would still try the cleaning as a start. Can you do this now and reply back?
Clean how? solvents, or disassemble?
Carb cleaner and a rag are best. Don't try to take it apart.
Great... You will be available for reply later... If this is the problem, I need to know how to reset, or will I need a scan tool? I am going to parts store now....
Take the battery cables off the battery, hold the ends together for 10 seconds then attach them to the battery and see what happens. This will reset the whole vehicle.
I will clean and get back to you
Bookmark this page so you can easily navigate back to it, and so you know, you can reply at any time for follow up information regarding this issue.
Clean, reset, check, then reply back to you?
Ok.... Cleaned throttle body and MAF, cleared codes, started fine, drove ok, I thought it had a little pull at stop idle in drive, got to gas station (about 5 mins), chimes and engine power down and engine light on again......
OK, then we are likely down to the throttle body then.
Well, if we had the code I could confirm for you. Did they tell you the code?
I don't know what code it is this time, I came back home assuming they were the same
So I need the codes again?
Yes, but if you had work done at a shop, then it should be on your work order.
No shop, got codes at auto zone
Ok, is there a way to get them again?
I guess I have to go back there and get them. I don't have a scan tool
Going to get them. Will check back when I return.
OK, sorry to make you go out again, but to be accurate we need those.
Same codes 1516, 2101 2176
It surges when you put it in drive, then engine powers down.
I already got all that from all data
Can the problem be with the APP sensor?
Ok, I was not sure if you had that. We always start with the lower numbered code and in this case it is the P1516 so it is the throttle then.
Plus that test info doesn't help me because I don't know where some of the components are
What does it mean "throttle body disconnected"?
BTW the blade is fine
Wait.. What is the blade's proper position?
With the key off, they should sit at about 25%
I am assuming the rest position is vertical, closed?
It means the throttle body unplugged.
Rest should be nearly closed.
25% open? It was totally closed when I cleaned it, but moved freely
OK, against spring tension?
Let me check the amount again.
It was tensioned when you moved it, yes, it would close itself
Ok, then that is ok, but the motors and sensors inside are not.
So I need a throttle body or sensors?
Throttle body. The sensors are integral to it and cannot be changed.
Check on eBay if you have time, the parts are often cheaper there.
That is definitely the problem?
I am 98% sure.
Ok. What do you think about used throttle bodies?
If it works, it is likely cheaper than new. I would try it.
Ok. Lets see what happens.
It is worth a shot.
Do you know if its the same for both V6 motors
No, the belts are different. Sorry, brain fart,
Yes, 12609500 is the number.
Is that all for today?
Yeah, I guess....
Ok great.. Thanks for your help