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I think I have purchased someone else's problems, I bought a 2002 C5 convertible corvette (beautiful car) got it home and right off the bat it has a parasitic draw, posted for help on that many thanks to guys that responded. So today took the car for a drive and when I went to give her a good dose of pedal the car went into limp mode throttle position sensor code came up as well as service traction control light. I have no idea what is going on with this car I am very frustrated to say the least. Any and all help would be greatly appreciated.
The code it gave was P1221 which is a throttle position sensor code, it started acting up after I drove the car for about 45 minutes and went to accelerate hard it went into limp mode.
The P1221 is a TPS 1/2 “correlation” DTC and not knowing if you own a DVOM you can remove the TPS sensor connector off the throttle body and also the 2 connectors from the TAC Module which is attached to the PCM and look for corrosion or water intrusion on all those connectors…you can start there…the TPS sensor are 2 potentiometers and when you press on the gas the signal voltage from the number 1 sensor goes low to high and number 2 goes high to low and if the 2 voltages disagree by a certain percentage the DTC will set…also check Fuse 17 in the underhood fusebox.
Just posted on another fellas post...but I will also post the same here...
If wrenching or diagnostics aint your thing...it's time to get that car to someone who can put a scanner on the car and look at live data. Anything anyone else says....me included...is just guessing without live data of what the car is DOING. Codes help...but without live data...codes are akin to discovering a ransom note which reads "We have your family...we will call you with further instructions." The $200 bucks you pay in diagnosis will save you the $800 in parts and labor or shotgunning parts at the problem until it goes away or cures...only to return cause the problem was never solved.
Sounds like you just got the car...which sucks but...old cars do wonky ****. This is part of the experience that is baked into it. That is not built in to ENOUGH of new-to-me sports car and classic car owners. I do my own work...so for me...this type of stuff while annoying...isn't very costly...minus time and beer lol Did you test drive the car under the same conditions the limp mod is occurring? And by test driving I dont mean around the block down the street. Is the previous owner still in the picture? I doubt this issue is appearing for the firs time. Sometimes after they have your money they are a wealth of information lol Get the car to a GOOD DIAGNOSTIC tech [ask around you local car community] and get the problem fixed. Hopefully it is not to costly.
I hooked up my Autel scan tool this morning and ran the car while watching the live data there were no problems with the tps code coming on when I revved the car. The only thing I did different yesterday was I turned the traction control off and tried to accelerate hard and thats when it went into limp mode. I have a c1278 code stored would this cause the car to go into limp mode and throw the tps code?
The 1278 is more of a “nuisance” code than anything…I see that DTC a lot on many C5’s I hook a scan tool up to…it will not cause a TPS code or cause the car to go into limp mode…the code info below so you can read what causes the code to set and what the car does when it sets…since you have a scan tool with the key ON look at TPS 1 and 2 voltages in live data..make sure that TPS1 and 2 voltages don’t drop out when pressing the accelerator slowly.
I drove the car but not for very long, I have taken the car to a mechanic and we will see what he can find out. I'm pretty sure the previous owner knew about the problems because he told me he had only owned the car for a month, that should have been a red flag right away, thanks for the info.
Will do, the mechanic was referred to me by another mechanic, he is supposed to be a pretty good electrical trouble shooter. I will let you guys know what he finds.
C5 Corvette Problems
