Howdy folks,

SO, my little jeep was starting to run just a bit rough. A small miss at idle.

I decided to change out bunch of sensors and now I cant figure out what is making it to run even more rough.

Ive changed:

Idle Air Control Valve
MAP sensor
CPS
TPS

Since making these changes the engine runs kinda rough compared to just a little miss before. Initially, after changing the sensors and valve, the motor ran great. But after just an hour or so of driving, it went down hill. Additionally, when I first start up the engine, it reves to 2000 RPMs and then comes back to about 800 and then begins to idle rough but still in the 800 range but it drops slightly when it hits the rough idle. It seems like the IAC has never really synched with the computer. If that makes sense.

Ive checked and I am not throwing any codes.

Was gonna start replacing the sensors one by one, beginning with the IAC.

Any other ideas on how to move forward?

 

I'm waiting on a TPS unit right now. After doing some research on TPS units I was only willing to spend the money on a MOPAR. Almost all of the other brands available for less money had pretty horrible reviews. I don't know what unit you put in or if it's causing your new issues but if you do another replacement I'd suggest the MOPAR.

Also recently swapped out the IAC. I had a stall on a hard right turn at low speed while braking. If you happen to have the old unit and it's not too difficult to swap you could try the old to see if you can at least return it to previous state.

Not exactly much in the suggestion category but thought I'd add my 2 cents. Good luck.

 

Agree with DoubleTap on the Mopar brand point. If you're replacing with anything but Mopar on those sensors the results could be questionable.

Given the description of the behavior, I'd definitely consider the IAC the first suspect. Put the old one back in and see if things improve. Be careful that the little o-ring on it is present and not buggered up, replace if necessary.

 

Thabks guys, I did use MOPAR part for the TPS but everything else is after market. I may have to go back and replace the new sensors with MOPAR parts. Working on another project now but next is the IAC and I’ll take it from there. Much appreciated.