P0121 Code
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Cruising
Joined: Mar 2023
Posts: 12
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P0121 Code
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.
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Welcome to the forum! You have come to the right place to ask all questions Corvette related....what is the P0121 related to?
Racer
Joined: Sep 2019
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3rd Gear
Joined: Mar 2023
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Who did the TT setup for you/what kit is it? I have a Cicio kit and have the same exact issue as you. I just clear the code when I hit a read light, and turn the car off then back on again to get the hesitation issue to go away.
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Cruising
Joined: Mar 2023
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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!!
Instructor
Joined: Nov 2011
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From: South FL (Fort Lauderdale)
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!!