Stumped

[Mcneer]

(97 TJ, 4.0, 6 cylinder) Engine will periodically get a rhythmic sound, rides rough during initial excelleration, less power, then fix itself. Any ideas?

 

[JPNinPA]

If it does this until the engine temp rises above 120 deg then it's likely the upstream O2 sensor. Unplug yhe O2 when this is happening and see if it goes away.
Check battery voltage or get it load tested and clean connections including the other side of the ground wires.

 

[Mcneer]

Thanks. Appreciate the help. I'll give it a try

 

[JPNinPA]

Another thing that is a good service item is cleaning your Throttle Body (TB) and IAC Idle Air Control. Here is a good link on how to. http://www.jeepforum.com/forum/f9/cleaning-iac-throttle-body-write-up-dummies-1114849/


Make sure you buy oem parts.