Okay... so my delemia with this damn TPS continues... I had my code scanned.. came up P0121.. which is the TPS sensor failure code. Replaced the TPS, replaced connecting wires, I have a pile of Skematics (thanks to the boys at AAMCO and RanWalk and Budhayes for their input ) and still cant figure out wtf is going on. So I have my boys at AAMCO checking it out.. they've had it for two days and tomorrow will be the 3rd.. i'm about to leave to check it out... but my question is... what else could be wrong to throw that code? Idk if the 01s have the acclerator pedal sensor... but i thought i heard of such a sensor before... what else could there be? I'm about to replace all the wiring for the TPS and see what that does. I was going to take it to the dealer.. but they will charge me out the *** while the guys at AAMCO now have already charged me and the problem happened again.. so they're 90-day warrenty covers that, so I dont have to pay anymore...

but any feedback would help.

Heres a link to the skematics I have right now if that helps...
http://truck.ls1tech.com/forums/showthread.php?t=342681

Thx in advance.

 

I think that the 01's with traction control have the throttle motors and acc pos sensors. I'm pretty sure that if you're not drive by wire, you don't have that sensor. Since the TPS has been replaced, I'm gonna guess that you have a broken wire or even a bad circuit in the PCM. Maybe one of the wires is backed out of the connectors either at the PCM or TPS.

 

well... I just got home and they physically took the pcm apart and looked at ALL the connections.. traced all the wires and no problems. I am going to do a few things tho... idk how it would help, but its something i HAVENT tried yet.. and that is: take the tb spacer out and put an maf back in there WITH the screen... i have a descreened one right now.

I also found out that the acc pos sensor AND the tsp are actually the same thing according to alldata.com... but idk what thats all about. And I dont have traction control either... so idk. I dont wanna rule out the computer itself... but hell its worth a try, if anyone has a stock 01 4.8L pcm send it my way and i'll give ya what you want for it and than just have it retuned for my mods by nelson this time...

but thanks again bud, anyone else have their input?

 

Might want to check all of the grounds in the front harnesses. I had a bad ground on one of them and it made my ABS and dash lights go nuts. When I would hit a bump all of my idiot lights would come on briefly, ABS light never came on but I braked hard once and locked up all the tires.

 

unless it is drive by wire the tps is all you got. you can check it out. i think it is the blue wire. get a meter and hook it to ground and then the pos lead to that wire. with the key on(engine off) move the tps. it should climb in voltage to 4.50 or near. at idle it should read in the .54 to .60 area. that will tell you that the sensor is good and that it is getting voltage. sounds as though the signal wire to the pcm is the actual failure.

 

How long after you installed the spacer did the light come on?

 

alldata.com is a wonderful thing!

 

 

Not sure really... maybe two weeks or so. Possibly longer. I'm going to try that next.

I drove it for 2 1/2 hrs straight last nite... not a single problem, no codes.

Than, as I'm leaving to do something productive today the light comes on and it starts up the same old bs again. I'm at a loss at this point.. still have no idea.

 

at idle what is the position of the blade? you should be at .06 i believe is where the computer wants it at.