still getting the P0220…

[clemenshess97]

Hey everybody,

last year I had a lot of trouble getting the reduced engine power message. I think it was the P2135 code. I replaced the throttle body, added a few grounds (neg battery pole to TCM to body to throttle body to engine to PCM), cleaned all thenother grounds on the truck and got the new throttle body plug installed. Since the temperature went up I got the reduced engine power message again, it seems to only happen when it‘s hot outside, it didn‘t occure during the winter time.
Now I get the P0220 code, not the P2135 and I don‘t know what else to do, some folks said that the TCM and the sensor in the pedal never go bad so I shouldn‘t replace those, any thoughts on that ?
I‘m going on a roadtrip to Denmark next week and all I can do right now is just delete the code with my little OBD2 scanner whenever the message shows up…but that is annoying.
It happens 1x-6x times a day.

Maybe someone has some more input for me trying to figure this out.

 

[rockola1971]

Your fault lies in either the TPS or your Pedal Position Sensor or associated wiring. Since your throttle body and I assume TPS in relatively new then I would likely look real hard at the Pedal Position Sensor for a dead spot in its voltage feedback on your scanner. Maybe even go as far as removing it and getting it on a bench and running it through its sweeps with an ohmeter connected looking distinctly for a dead spot which likely will be your city speed or highway speed position that is dead. Is there a typical speed at which you usually get this reduced engine power DTC?

 

[Fless]

In addition to the suggestions by @rockola1971, carefully inspect the wiring near the throttle body. The wires going to the TB can break underneath the insulation within a foot or so of the TB. Flex them and inspect for internal damage.

If your scanner will graph your PPS then run it through a sweep to look for dead spots. Otherwise an analog VOM is the perfect tool to use to manually test the PPS.

 

[clemenshess97]

it throws the code at different speeds, had it happening in the city doing 30km/h but also doing 140km/h on the autobahn, it even sometimes throws the P0220 code when putting the key in the ignition.

The wiring near the throttle body is fine, I replaced it last year and I also just did the wiggling test.

 

[exp500]

Have you seen these tests?-

How To Test The GM Accelerator Pedal Position (APP) Sensor 1

GM 4.8L, 5.3L, 6.0L Index of Articles

easyautodiagnostics.com

How To Test The GM Accelerator Pedal Position (APP) Sensor 2

GM 4.8L, 5.3L, 6.0L Index of Articles

easyautodiagnostics.com

 

[clemenshess97]

Have you seen these tests?-

How To Test The GM Accelerator Pedal Position (APP) Sensor 1

GM 4.8L, 5.3L, 6.0L Index of Articles

easyautodiagnostics.com

How To Test The GM Accelerator Pedal Position (APP) Sensor 2

GM 4.8L, 5.3L, 6.0L Index of Articles

easyautodiagnostics.com

Thanks, haven‘t seen this one yet.

 

[GreenTahoeZ71]

Thanks, haven‘t seen this one yet.

I don't think i have either.
I am actually fighting this exact same problem almost verbatim to what you described.

I actually went further and replaced the entire 16 wire harness to the TAC with the proper Delphi pins and connector ends I got from EFi Connections. I also replaced the TAC to pedal harness as well with one they had pre-fabbed. I also got a refurbished PCM that was supposed to have the newest calibrations of which one was specifically for the P2135 voltage disagreement code.
I also redid the grounds like you said with new ends and heat shrink. I even opened the engine harness to install the 16 wire TAC module harness back like factory. I also bought the low adhesive wire harness tape. I also did new battery cables too.
I have even been re-pinning the PCM and the harness ends that plug into the underside of the fuse block.
I also just discovered I had an alternator that was overcharging my system for the past three years. I finally got that sorted by taking out back to Auto Zone and getting a Remy one that is now putting out the right volts. I also redid the connector that goes to my alternator with ends and terminals from EFI Connections.
It is the single most frustrating thing I have ever dealt with.

The weird part is that it began after I had my front right ABS wheel speed sensor replaced. Only the wire part that plugs into the wheel cylinder. It was broken when I got the truck making my ABS light stay on. It started with the P0220 first. Now almost three years later and all that work and I'm still getting P0220 and P2135. Sometimes together, sometimes not. Sometimes driving, sometimes when I crank up.
I just find it hard to believe that there is no solution when the truck went for almost three years before that without doing it.
I may unplug my wheel sensor again to see if it stops.

Please do post back if you find something and I will do the same.

I will look at the guide posted as well.

These are the pics of the new TAC to pedal harness and the new throttlebody plug end I made and picture of me crimping one of the new sealed terminals for the blue inline connector pictured. I had no idea they made so many terminals and crimp tools. And my engine harness all opened up !

I mean it definitely runs better now except for this God forsaken problem.

 

[tomloans]

Has anyone come up with a solution? Also guys the wiring between the accelerator sensor and throttle body sensor has to be flawless. Meaning, the slightest misconnection can cause the reduced power garbage. If you replace the harness, you really need to solder the connections between the wires. I had this problem and soldering the connections ( very carefully ) solved it. But now 5 years later, it is back! I have a new throttle body and it didn't do any good at all. Switched out accelerator sensor with a known good one and no go either. So somewhere I have a connection loss among the wiring I have to locate I guess.

 

[Slow yukon]

Your fault lies in either the TPS or your Pedal Position Sensor or associated wiring. Since your throttle body and I assume TPS in relatively new then I would likely look real hard at the Pedal Position Sensor for a dead spot in its voltage feedback on your scanner. Maybe even go as far as removing it and getting it on a bench and running it through its sweeps with an ohmeter connected looking distinctly for a dead spot which likely will be your city speed or highway speed position that is dead. Is there a typical speed at which you usually get this reduced engine power DTC?

I have same issue I got the p0120 p0220 p1516 p2135 I changed throttle body, pedal sensor, and even changed the throttle body pigtail harness. Even tried a different TCM. Still reduced engine power. And it sometimes doesn’t happen driving either. When I put the key in the run position it already appears. Sometimes driving also. Did you ever get it d fixed?

 

[tomloans]

This is almost always a ground or connection issue if you have changed out the throttle body and pedal sensor. First and foremost is that the throttle body needs to be ACDelco! 2nd is that be sure that the battery terminals are solid and tight. Wire brush these as well. 2nd, pigtail harness wires needs to be soldered. Yes really. Don't ignore this. Really I mean it!!! Also, there are 3 or four grounds under the drivers seat under the belly. Crawl under and you will see one screw with numerous ground wires to it. Take all off and wire brush the plate to which they are connected front and back. GMC sprayed the bottom of the vehicle then attached the grounds. Super stupid. remove the coating that they sprayed on. You will see what I mean when you get there. be methodical on all of this. Then wire brush all wires and add dielectric grease so you wont have to do it again. Don't just look and say it is fine! Be like Nike and "just do it"! Next grounding issue and very important is the passenger side behind the engine and next is the drivers side ground. Watch these videos and get it done right so you have no issues anymore.