I recently changed plugs, plug wires, cap and rotor, and replaced the valve cover gaskets. On my way to work the next morning I threw a P0122 DTC-low tps volt. The truck started bucking after stopping not bad just a little surge. I replaced the TPS and cleared the code 15 min later tripped again. I thought maybe I didn't clean the ground good enough when I replaced the gaskets, cleaned that up cleared the code and reinstalled old TPS. It hasn't thrown the code yet but it surged a little today and probably will soon. Any suggestions would help.

 

i would check your Idle Air Control...it bolts onto the back of your throttle body.....take it off, dont touch it, just spray with cleaner until clean.....and check your wires

 

yep thats my next plan of action to go through the other sensors. I was hoping some one else has had the same issues so that I could go to the source without doing a bunch of diagnosis

 

so it was fine before all of this? you might also try the plug wire reroute.....it can give you funky codes....

http://dodgeram.info/tsb/1998/18-48-98/18-48-98.htm

 

I was wondering about plug wires and had planned on trying that re-route. I'm not sure if it was happening before I changed everything. I do recall that it felt like it sputtered one morning so I think that maybe that may have been the first failure but I don't know.

 

Remove the whole TB and sensors and clean it all. And if you bought a cheapo TPS from Autozone or wherever they suck. So don't buy an IAC from there either.

 

i tried to outsmart the pcm one time by ignoring a P0123 tps related code. bad idea, as the pcm is smarter than i am. replacing tps fixed my problem.

check the wiring on the tps plug and harness, make sure you didn't break a wire somewhere along the way.

if you haven't fully reset the pcm, do that. disconnect neg battery and turn ignition to start for 30 sec.

the pcm is unhappy with a low voltage signal from the tps. don't ignore it. probe the tps pins with a volt meter. there is a thread for it... make sure your voltages are as they should be. an old and a new tps throwing the same code is suspicious.

 

I have replaced TPS and it still have the same code P0122 trip. Ill clean everything and let you guys know.

 

anyone know how to check the IAC and MAP sensors

 

iac- unbolt it with it still plugged in and have someone turn the truck on (don't start it, just turn the key to "on") and the pintile should move in and out, if it doesn't it is stuck could try cleaning it with some TB cleaner (unplug it and clean off the truck). don't twist/push/pull the pintile or it will break.

map- if you can get it to idle smooth for a minute, tap it with a screwdriver handle or something else that is hard plastic, but don't tap it hard, just about as hard as you would knock on a door, if its bad then the idle will jump all over the place and it'll seem like the engine is having a seizure.