P0123..AGAIN!!

VenomTruck

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Columbia SC
Just replaced the TPS a few weeks ago, and today Im sitting at the Benz dealership and bam, a CEL comes on. Truck started idling like shit and felt like it was misfiring. I knew exactly what it was. Floored it for about 2 seconds and then it drove fine, which is what I expected. Went home and got the SCT and yep, TPS voltage too high. The only thing different about today was its hot as hell outside and I had my son in the car, so I had the air on high and it was at idle for about 10 minutes while I was talking to the sales guy. When I replace the TPS, am I missing a step? Its just out with the old, in with the new right? Replacing these little buggers is getting old. Any help or suggestions would be great.

Heres the Benz Im thinking about getting.



 
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Disconnect battery, disconnect PCM, replace TPS, hook battery and PCM back up, turn on key, press throttle down/up twice (slowly) and then start it up.

If you continue to have issues I would pop the hood and play with the wiring while the truck is running to see if you have a short in the TPS circuit.
 
Check the IAC, I know looking around hear if the TPS is acting up the IAC is sometimes a contributor

You may also want to try resetting your idle since you switched the TPS
 
Ill give it a shot, all these sensors suck, I wish we could just get rid of them.
 
PO123.... Don't really care.

You gonna get the AMG? :D
 
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Lol, gonna crunch some numbers. The manager personally wants my truck, bad. I told him when you get something worth while gimme a call.

make sure you get rid of the chuck tune and the nasa exhaust. I can imagine you making atleast 1200 hp and you wouldnt want anyone to get hurt.
 
Did some messin around. Unplugged the TPS and IAC, pulled them out and inspected them. The problem is the IAC. Everytime I pull it out :D the arm is ALL the way out. I push it back in, not forcing it, and the truck runs fine. I checked and I have zero build up, gunk, that might be getting in the way. I also did a hard reset and all that other shit. But, on more than one occasion, when I put it in park and let it idle for 5-10 minutes, thats when it happens. I know its the IAC because I didnt even replace the TPS. Just unhooked it. Also, this is my second IAC. When I was at tonys shop we were talking about this same issue and he had an extra one that he just gave me :rock: Just annoyed at this point… Any thoughts? Wiring issue?
 
Throttle body? What kind? Check your idle (key on/engine off at brwn/orange wire on TPS. Report back soldier!
 
Roger that! Stock throttle body. And Ill also add that the trucks idles nice and smooth until the arm on the IAC is all the way out, then its obviously not getting enough air. Isnt there an IAC delete mod out there??
 
Roger that! Stock throttle body. And Ill also add that the trucks idles nice and smooth until the arm on the IAC is all the way out, then its obviously not getting enough air. Isnt there an IAC delete mod out there??

You can delete IAC but sometimes it has tough times recovering to idle or idling/cruising with AC on, etc. See what that voltage reads.
 
Ill have to wait to check the voltage, seems strange you mention the AC being on, in the OP I stated that the AC was on high when this happened, just a coincidence?
 

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