P0121
Thread Starter
Cruising
Joined: Mar 2023
Posts: 12
Likes: 0
P0121
Hello all. I have a modified 2020 C8. Twin Turbos. I have been dealing with the code P0121. This happens when I jump on it. Regardless if it is from a standing position, or rolling. If driving normal, no issues at all, but this car is not designed for normal driving. I know when the car throws this code. When I slow down to normal speed, and drive normally, the car starts this hesitation thing. Very sporadic in natural if you will. Then I know. First thing, I plug into the OBDII with my new Launch X431 Pro 3S scan platform, scan for any codes first to make sure this is the code, 100% of the time it is, Then, I reset the code. Give it a minute. Start driving. Runs like a champ. Until I repeat as described above. I cannot get any where with the shop that did all my work. I have 20,000 miles on the car. I really need some help. Are there any suggestions or recommendations? Thank you.
Thread Starter
Cruising
Joined: Mar 2023
Posts: 12
Likes: 0
Yes. I just ordered.16-22+ Camaro SS & 20+ C8 Corvette LT2, 92MM Throttle Body, BBK × 1 , and was planning on replacing my stock with this one to see if a larger throttlebody would help. Seeing that I have introduced a tremendous amount of additional air with the TwinTurbo’s. Just shooting in the dark really
Melting Slicks
Joined: Feb 2000
Posts: 3,420
Likes: 565
From: new orleans
You may want to call Pietz performance in Houston, he does a lot of these and has provided some help in the past. How much boost are you running? sounds like you need one of the piggyback tuning boxes.
Burning Brakes
Joined: Aug 2004
Posts: 847
Likes: 729
From: Houston, TX
In addition to Peitz, LMR (LateModelRacecraft), JoTechRacing, and Cicio Performance have done many Twin Turbo installations. Perhaps one of them has run across your problem.
Who did your installation and how long ago? Is it an ETS twin turbo kit? If so, ETS might also be worth calling.
Did it just recently start throwing the Codes?
Who did your installation and how long ago? Is it an ETS twin turbo kit? If so, ETS might also be worth calling.
Did it just recently start throwing the Codes?
Last edited by INTRUDR; Mar 10, 2023 at 09:27 AM.
Thread Starter
Cruising
Joined: Mar 2023
Posts: 12
Likes: 0
So, Lethal Performance in San Antonio did the shop work, but Pietz out of Houston did the tuning. Not a normal computer tuning, but module tuning. I had to wait about a month after my transmission, clutch, new fuel system was either rebuilt or replaced before I was able to get the Delta module I believe it’s called. He was tuning it. Evidently, my guy has talk to Pietz, and he’s going to reprogram the module.
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Thread Starter
Cruising
Joined: Mar 2023
Posts: 12
Likes: 0
Sorry for the late response. Still nothing. My installer came to the house to download the DCM file to give to Peitz. Now waiting on him to come get my car and take to his shop to work with Peitz on retune. Did you fix your issue? I can run the car all day, but cannot get full throttle, or it will throw the code and drive like crap until I reset. Very frustrating.
Thread Starter
Cruising
Joined: Mar 2023
Posts: 12
Likes: 0
My guy came to the house and downloaded the tuning to send back to Peitz. I am hoping it is just a retune fix. I will keep you posted. Peitz supplied the module and tuning. I can allows clear the code, and wait for the car to reset, then works great. If i drive like my grandmother, i have no issues. As soon as I get on it, it will throw the code, and the car starts running like crap. Rinse and repeat!!
Thread Starter
Cruising
Joined: Mar 2023
Posts: 12
Likes: 0
Yes. Stock throttle body. I just responded to another post. Peitz supplied the DCM. I cannot imagine it could be anything else, but this. My installer came to the house and downloaded the DCM file to send to Peitz. Waiting on him to get the retune from them so they can work on it. Will keep you posted. Any other suggestions? TY
3rd Gear
Joined: Mar 2023
Posts: 3
Likes: 0
I am still living with it. I can get one decent pull in and then it throws. Cruising at highway speeds doesn't seem to be an issue when the code is thrown but 1st -> 2nd and 2nd -> 3rd the car is super hesitant.
reached out to trifecta to see if they would help out since they apparently have the ECU cracked but didn't get a response. Guessing they have some exclusivity deal with procharger.
reached out to trifecta to see if they would help out since they apparently have the ECU cracked but didn't get a response. Guessing they have some exclusivity deal with procharger.