NEED HELP 04 GMC SIERRA 1500 5.3L FLEX FUEL V8 LIMP MODE with P0220, P2101, & P2135

[turbee3]

AS I SAID ABOVE MY 04 GMC SIERRA 1500 5.3L FLEX FUEL V8 2WD ALL OF THE SUDDEN WENT INTO LIMP MODE TODAY! THANK GOD I HAD NOT MADE IT VERY FAR FROM HOME BECAUSE THE ACCELERATOR PEDAL WASN'T DOING ANYTHING AT ALL, EVEN PRESSING IT ALL OF THE WAY DOWN TO THE FLOOR MADE NO DIFFERENCE!! AFTER I FINALLY LIMPED IT/MY WAY BACK HOME AT ABOUT 20MPH I BROKE OUT MY DIABLOSPORT I3 PLATINUM TUNNER TO READ THE TROUBLE CODES AND IT IS SHOWING A WHOPPING THREE DTC's ALL AT THE SAME TIME, WTF??!! HERE THEY ARE IN ORDER DOWN BELOW!

P0220: Throttle/Pedal Position Sensor/Switch B Circuit.

P2101: Throttle Actuator A Control Motor Circuit Range/Performance.

P2135: Throttle/Pedal Position Sensor/Switch A/B Voltage Correlation.

SOMEBODY, ANYBODY OUT THERE THAT HAS WAY MORE KNOWLEDGE WITH ISSUES LIKE THIS THAN I DO OR ANY KIND OF CLUE AS TO WHAT IN THE HELL I'M FACING HERE WITH ALL OF THESE TROUBLE CODES AND THE LIMP MODE PLEASE, PLEASE, PLEASE HELP ME OUT WITH YOUR ADVICE ON WHERE TO EVEN START/BEGIN LOOKING OR WHAT COULD BE CAUSING ALL OF THIS SHIT TO JUST HAPPEN OUT OF THE BLUE LIKE THIS?? I MEAN IT WAS RUNNING JUST FINE YESTERDAY AND EVERY DAY BEFORE TODAY WHEN THIS ALL OF THE SUDDEN HAPPENED, THEIR WAS ABSOLUTELY NO WARNING AT ALL THAT SOMETHING WAS GOING ON/ THAT MY TRUCK WAS ABOUT TO GO CRAZY ON ME LIKE THIS!!!! ANY SOUND ADVICE WOULD BE VERY VERY GREATLY APPRECIATED BECAUSE I JUST DROPPED RIGHT AT 8 GRAND FOR A PROCHARGER HIGH OUTPUT INTERCOOLED SUPERCHARGER SYSTEM FOR MY TRUCK ON 05/13/2022 AND WHAT I'VE GOT LEFT OVER FROM THE MONTHS OF SAVING UP FOR IT ARE GOING TOWARDS HAVNG IT INSTALLED, TUNNED, AND DYNOED!! SO I DON'T HAVE THE $ TO SPEND ON A RIDICULOUS MECHANIC BILL RIGHT NOW UNLESS I'VE ABSOLUTELY GOT TO!! IN WHICH CASE I WOULD MORE THAN LIKELY HAVE TO PUT OFF HAVING MY BRAND NEW PROCHARGER KIT INSTALLED AND EVEN THINKING ABOUT THAT POSSIBILITY MAKES ME WANT TO CRY!!!! SO I AM ABSOLUTELY BEGGING FOR ANY ADVICE AND HELP THAT ANY OF YOU OUT THERE CAN OFFER TO ME!!!! THANK'S SO MUCH FOR EVEN TAKING THE TIME TO READ MY THREAD AND HOPEFULLY GIVE ME ANY HELP THAT YOU POSSIBILITY CAN TO HELP ME FIGURE THIS CLUSTER FLOP OUT!!!!

THANK'S AGAIN, JORDAN T!!!!!!

 

[Mooseman]

Moved your thread to the proper section and shortened the title. Please DO NOT USE ALL CAPS!

The limp mode is for your protection to prevent runaway engine situations when there is an issue with the drive by wire throttle system. There is obviously an issue there. The first one says there is an issue with the circuit. Grab the schematics for your truck (check my signature for the link to them) and check each wire from the pedal sensor and throttle body to the PCM and grounds. That may be what's causing the other codes. If they check out, then check the manual on how to verify the pedal sensor or, it you want, you can shotgun it by replacing the pedal sensor, and if that doesn't work, replace the throttle body.

Also check which other systems connect to that same 5V reference line. If this other system has issues, it may effect the throttle system. We see this often on the GMT360 from the fan clutch.

 

[azswiss]

Had similar issues (P0220, P2135) with my '03 Suburban FlexFuel (Z) 5.3L with 136K miles.

After first clearing the DTC's I disconnected the battery for 15 minutes (clear/reset the TPS cals) and then retested; no codes. Was OK for a day or so but then the codes came back. Repeated the whole cycle 2 more times over the next several days. No joy.

These DTC's typically point to a problem with the throttle position sensors located inside the electronic throttle body. Here is a good link on diagnosing a P0220 problem by testing the sensors with a multimeter:

P0220 TP Sensor B Circuit Malfunction (With TAC Electronic Throttle Body)

In my case, TPS1 resistance values were way out of range and TPS2 was showing non-linear and inconsistent results.

I replaced the throttle body (it was the original) and have been problem free for 5 years/40K miles.

Note, the only unit I could get locally was the Hitachi EBT0019. The body casting was identical to that of the AC Delco original, right down to the part code identifiers.

Rock Auto has them both and the prices are within $5.

Edit: Given the option, I would always go with the AC Delco original part.

 

[turbee3]

Moved your thread to the proper section and shortened the title. Please DO NOT USE ALL CAPS!

The limp mode is for your protection to prevent runaway engine situations when there is an issue with the drive by wire throttle system. There is obviously an issue there. The first one says there is an issue with the circuit. Grab the schematics for your truck (check my signature for the link to them) and check each wire from the pedal sensor and throttle body to the PCM and grounds. That may be what's causing the other codes. If they check out, then check the manual on how to verify the pedal sensor or, it you want, you can shotgun it by replacing the pedal sensor, and if that doesn't work, replace the throttle body.

Also check which other systems connect to that same 5V reference line. If this other system has issues, it may effect the throttle system. We see this often on the GMT360 from the fan clutch.

Ok, thank you so much Mooseman for doing all of that for me sir, you're a true gentleman! This is/was my 1st thread/post and I wasn't exactly sure where to post it at so I just took a stab at what I thought looked like the best one at the time! Sorry about the all caps too, I was just in that freak out mode when I wrote it so that's where the all caps came from😱🤭!!

Thank you as well for the information you provided, I will start there. Another thing I forgot to mention was that the engine in my truck is not the factory engine. It came from the factory with a NON flex fuel 5.3L V8 but I trashed that sucker and had to replace it about 4 year's ago now! I didn't really want to put a flex fuel engine back into my truck but that was all that my mechanic (that I was using at the time) could get his hands on that had very low mileage on it, all of the standard non flex fuel engines had way way over 100k miles on them and the flex fuel engine I had installed only had like 25k on it. I don't know if this makes any difference or not, I just forgot to mention it.

I also had an issue with my truck going into limp mode intermittently about two year's ago. It would only do it on warm/hot day's and every now and then but when it was doing this back then I never had an issue with the gas pedal not working, the truck still drove (although running very crappie) and the gas pedal still worked as it should, that is it wasn't completely dead like it was yesterday. This went on for over a year with different DTC's popping up at different times so it was really hard to nail down! I finally did enough research and threw enough part's at it to find out that it was likely one or both of my knock sensors so I had both of them and the harness replaced late last year and that stopped it dead, no more reduced engine power/limp mode or DTC's until yesterday when this new situation happened. Not sure if any of this matters I just figured I'd mention it just incase! Thank's again Mooseman for your suggestions👍!!

 

[turbee3]

Had similar issues (P0220, P2135) with my '03 Suburban FlexFuel (Z) 5.3L with 136K miles.

After first clearing the DTC's I disconnected the battery for 15 minutes (clear/reset the TPS cals) and then retested; no codes. Was OK for a day or so but then the codes came back. Repeated the whole cycle 2 more times over the next several days. No joy.

These DTC's typically point to a problem with the throttle position sensors located inside the electronic throttle body. Here is a good link on diagnosing a P0220 problem by testing the sensors with a multimeter:

P0220 TP Sensor B Circuit Malfunction (With TAC Electronic Throttle Body)

In my case, TPS1 resistance values were way out of range and TPS2 was showing non-linear and inconsistent results.

I replaced the throttle body (it was the original) and have been problem free for 5 years/40K miles.

Note, the only unit I could get locally was the Hitachi EBT0019. The body casting was identical to that of the AC Delco original, right down to the part code identifiers.

Rock Auto has them both and the prices are within $5.

Edit: Given the option, I would always go with the AC Delco original part.

Thank's for your reply and your info mr azswiss!

I forgot to mention that the engine in my truck is not the factory engine, my trucks factory vin code is T. My truck came from the factory with a NON flex fuel 5.3L V8 but I trashed that sucker and had to replace it about 4 year's ago now! I didn't really want to put a flex fuel engine back into my truck but that was all that my mechanic (that I was using at the time) could get his hands on that had very low mileage on it, all of the standard non flex fuel engines had way way over 100k miles on them and the flex fuel engine I had installed only had like 25k on it so I let him do it. I don't know if this makes any difference or not, I just forgot to mention it.

I also had an issue once before with my truck going into limp mode intermittently about two year's ago. It would only do it on warm/hot day's and every now and then but when it was doing this back then I never had an issue with the gas pedal not working, the truck still drove (although running very crappie) and the gas pedal still worked as it should, that is it wasn't completely dead like it was yesterday. This went on for over a year with different DTC's popping up at different times so it was really hard to nail down! I finally did enough research and threw enough part's at it to find out that it was likely one or both of my knock sensors so I had both of them and the harness replaced late last year and that stopped it dead, no more reduced engine power/limp mode or DTC's until yesterday when this new situation happened. Not sure if any of this matters I just figured I'd mention it just incase!

Again, I really appreciate your help and advice mr azswiss! If you think that any of the extra info I provided might make any kind of difference please just let me know! Thank's again, Jordan T!!

 

[azswiss]

No additional info required right now. Rather than going after the problem with the parts cannon just systematically work through the diagnostic process. Listen to what the truck is telling you (DTC's, multimeter measurements, etc.) and you will get there.

 

[flyboy2610]

I don't know if the Sierra's use the same type of electronic fan clutch as the Trailblazers and Envoys, or if they share the same 5 volt reference circuit. On the TB's and Envoys (at least the earlier ones with the electronic fan clutch) a failing fan clutch will send the vehicle into limp because it degrades that 5 volt reference circuit, which is also used by the throttle position sensor. The PCM will send the vehicle into limp mode as a precaution against a runaway throttle, because it doesn't know where the throttle actually is.
I said all that to say this: If you do have an electronic fan clutch, you might try unplugging it and see if that cures the issue. Keep a close eye on the coolant temperature, though, and I wouldn't recommend running the AC while trying this. If it cures the problem, replace the fan clutch.