First off i own a 2001 dodge 1500 5.2, So i keep looking everywhere and cannot seem to find someone with the same issue, my tps voltage seems low even a brand new one, around 3.7 at WOT, however after a month or two after replacment the WOT voltage drops to around 3.2 or so. Why am i not getting more so around 4.5 volts at WOT? Also im getting about 8-9mpg per tank(city/highway) sluggish performance until about 3000 rpm then it feels like i hit the powerband in a 2-stroke dirtbike. Has trouble mintaining speeds up inclines in overdrive on the highway. I hear a "sucking noise" like a vaccuum leak on cold startup, goes away after warms up and disappears upon acceperation while cold. I am thinking of removing forward o2 sensor and driving to see if the cat is clogged and i want to replace spark plugs with better ones. My muffler is currently cut off so i have cats only. Maybe im losing back pressure along with the ****ty stock 3.55 gears(want to change to 4.10s when funds available) can anyone shed some light on my issues or point me in some tood directions.

 

Did you happen to test the supply voltage? What brand sensor? Do you have any codes?

 

Im sorry to sound like a noob but would i trace the 5volt wire back to the pcm and test it there?

 

Sorry yes i did test supply its getting about 5.12 volts, im pretty sure at one point i had a tps low voltage code and i have tried a few different sensors, one from advance auto and one from o'reileys whatever their brands are.

 

Need to see if source voltage is bleeding off, causing sensor return voltage to also fall off.

That's a strange one though...... does it do that at idle?? Or only with the throttle open to some degree?