Rough-ish idle

[cdeleo]

Trying to track down a few problems on my XJ, one being the rough idle. My rpms barely jump when at idle but the best description I have is the engine sounds like that guy next to you in traffic with a lot of bass, the engine sounds like it cuts out for like half a second but it does NOT turn off. Could it be something to do with my coolant? I don't have enough in it and it is dirty but I barely drive it so I haven't gotten around to flushing the coolant system yet. I do have a CEL on for something with a fan relay, not sure the code because my buddies reader was able to show the code, mine is a cheaper reader that doesn't show everything.

 

[RCP Phx]

My 2000 acted that way when the cam sensor was going out. That followed by the CPS and do yourself a favor and only buy Mopar sensors.

 

[Tim_MN]

Are all of the tune-up parts fresh ? Have you tested the ignition coil ?

Fix any known failures and Check Engine Light trouble codes. You can't properly diagnose things with known existing problems.

I add a bottle of fuel injector cleaner to a tank full of gas every 4-6 months on both of my XJ's. They will often remind me with a rough idle when it is time once again to buy another bottle.

The Jeep in-line 6 cylinder engine has never been known for its smooth idle, you should sit in my 84 CJ-7 at a stop light one time.

 

[cdeleo]

My 2000 acted that way when the cam sensor was going out. That followed by the CPS and do yourself a favor and only buy Mopar sensors.

Could this cause a lurching feeling at ~40mph? This problem started around the same time as my idle problem

 

[RCP Phx]

I did not experience "lurching", mine would just mysteriously cut-out for a second or two.