1996 ram 1500 4x4 5.2L auto has just had a complete tune up, including a new MAP Sensor. The vehicle would some times stall but most times it just had erratic idle speed. I cleaned the throttle body and the IAC motor and chamber. The vehicle ran better but the idle was still up and down sometimes and it stopped stalling for the last 3 months. In the last couple of days the vehicle stall on the highway after about 15 mins if driving. I was able to start it up right away. I would put it into drive and as long as i didnt touch the gas the vehicle would idle good, but as soon as i touched the gas it would spit and sputter and usually stall. For the hell of it i tried reverse and i could go backwards with the truck revving at 3000 RPM, no spit, no sputter, and it would run smooth. Checked fuel pressures and for vac leaks,all good. Going to check the evap system. I drove backwards with the truck for nearly 20 mins and the truck did not miss a heart beat. Forwards on the other hand is a different story. I can drive it forwards for about 15 mins and it run so smooth, then it stalls. Any ideas?

 

Welcome to DF!

IAC isn't worth cleaning, in my opinion. Others here will disagree with me on that though.
Replace the TPS (throttle position sensor). Its even cheaper and easier to replace. Best ones are actually from the dealership, but are less than $20 last time I checked.

Then disconnect the battery for a while. This will reset the computer to force it to learn the new sensors. If you don't do this, it will try to function off data from whichever sensor was malfunctioning, and will still run funny. I had a TPS sensor go out on my 2001 Ram back when I had it. Put a new one on and started it without reseting the computer. My idle was at almost 2000 RPM. I reset the computer, and she was as good as new.

If you still have the issue, then replace the IAC.

For future reference on where to post new threads:
https://dodgeforum.com/forum/dodge-r...ead-first.html

 

If cleaning the TB and IAC didn't help, then yes you need a new one. And don't cheap out on it. Get a Standard Motor Products brand or one from the dealer. And please remove the negative battery cable next time, before, cleaning or replacing any sensors.

And get a Haynes manual, and a cheap multimeter. With those 2 things you can test most if not all the sensors, like TPS for instance. Not to mention the other valuable info you'll find in the manual.