Is there any other general sensors I might try to replace for a TPS code (P0121).

So far I replaced the TPS sensor, IAC, tried a new MAF, and a new intake. Still throwing the code on occasions. Is there some type of speed sensor? And its not in the tuning. Ive switched pcms three times since than and had it tuned by different people.

 

More then likely its not any sensors that are bad, it sounds like the wiring to the TPS has a short or to much resistence. Get a wiring diagram and test for voltage drops in the circuit, thats where you will most likely find the problem.

 

oh yea, forgot to add that I did that as well. The code will only come up when sitting still for long periods of time in drive. It will not come on, however, if i keep my foot in it while stopped and have it stalled to like 1 grand or more.

 

Have you messed with the TPS in anyway before the code? New TB? Anything. The code reads as insufficient response from the TPS sensor. It just means that the pcm doesn't like the "actual" response versus the "predicted" response. Just like the nbo2's looking for particular ranges (predicted) and not getting it since the exhaust is cooler than "normal". Both codes happen at idle or even start up.

I saved this link in my favorites, it helped me out when I had my TPS sensor issues, I have HPT so my problem was solved by resetting/zeroing the tps. Mine was reading like 1 to 2% at idle. Read this dtc trouble shooting LINK. It is for a F-Body 98, but it helped me. I am sure somebody will chime in with a more specific search result for our trucks if needed.

 

that makes perfect sense than. When this happened i had a tb on here with the bump stop mod.. that would make up the difference between the predicted angle and the actual angle... and than when i put the new tb on it didnt reset itself... i'll have to get Jerry to zero those tps tables out...

where is the tps stuff located in HPT? Thats what we are using

 

https://ls1tech.com/forums/showthread.php?t=177230

I didn't zero any tables...I "reset" the tps position. This thread from tech pretty much nails it down. As you know, case by case is different and may require tweaking in different ways.

 

alrighty, thanks. Also, reseting the tps... cant i just turn the key on, pull the tps out for 15-30 sec, turn the key off, put the tps back in and than turn the key back on? or does this HAVE to be tuned (My tuner lives in Marietta which is an hour from me, so thats why i ask)

 

hmmmm...I really don't know the answer. The thread link I gave is really for another way of helping idling issues but helps with "resetting" the tps position. What's to hurt trying? Makes some sense that it might work (giving that's the problem). Try and report back!

 

I tired it and so far no problems.. but I cant remember if I had did that or not yet. Sometimes i'll do this and it'll come back eventually... i'll try not two footing it today and see if it acts up again. If it does, than i'll just have to mess with it in hptuners.