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P0121 Code and Trans not shifting correctly

Stappen720

New member
so i finished installing my trans and im now having problems with the trans not shifting gears correctly. It sometimes skips gears and sometimes feels like 1st gear revs longer than its suppose to to shift into 2nd. I also got a SES light that says P0121 - Throttle Position Sensor/Switch A Circuit Range/Performance Problem. So i changed the TPS and its still doing the same thing. On my HP tuners vcm scanner it says my IAT is running really hot at idle. I have never seen it pass 105* at idle and its hit 172* degrees. Im also noticing that my boost gauge isnt working now and my blow off valve isnt blowing off. So i checked vacuum lines and i havent seen anything unusual, or hear any unusual sounds to me. One thing i noticed is that when i rev the engine my boost bypass doesnt open up but i cant remember if it ever did since i went turbo. Hoping to get someone who has a turbo for that question. Also when i accelerate in park slightly the peddle stays accelerated and slowly drops down. When i looked up what symptoms the TPS does it did say something about that happening. After i changed TPS i didnt really drive to far but i didnt get any codes for it yet. Any questions ask please. thanks guys
 


it shouldnt have to be tuned. I only changed it out because the converter was junk. Worked fine before. Its a Triple Edge Performance trans. Converter was upgraded to the billet converter. I think im missing something from re-installing trans. I feel like the car isnt getting any boost. And since my boost gauge isnt working i kind of believe it.
 
hey bill.... haha i already read that before you sent that to me. I looked up that code on google. ok so i have checked everything possible for loose vacuum lines , looked for cut wires, grounds are tight. Since i changed my TPS sensor i have not seen any service lights for 5 minutes of driving. I have factory boost gauge and a seperate boost gauge and neither of them are working. The blow off valve is not working either. The car feels like it has absolutely no boost whatsoever. Im lost on this one now.
 


took the car for a test drive and now i have code p0171 - system to lean bank 1 . I havent had time to check over things for this code. Ill try tomorrow.
 
u guys are gonna laugh. Ended up being my intercooler pipe blew off. Happend to me twice. Clamp ended up being junk so i had to buy new ones. Everything works great just needs a sweet tune now.
 
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