2001 Cherokee XJ idling issues

Hey there,

I have a 2001 XJ classic with about 103,000 on the odometer. I am the second owner and have only had it for about 5000 miles. It started to idle pretty rough and has a loss of power on acceleration. I am not super familiar with these 4.0l engines but I tried the CPS, the coil pack, and fuel injectors. The problem has not gone away, and the PCM is throwing cylinder misfire codes. Three at first, cylinders 2,3 and 5. Since this work it has just thrown a code for cylinder 6. I also changed the oil and put some sea foam in the fuel. Not sure where else to go from here and was hoping for some suggestions on what to look at next. Thanks

Hmm...

Do you know anything about the maintenance history on this thing under the previous owner?

When you swapped the coil pack, did you pull/check the spark plugs? If not, might be worth a look. Heck, maybe just get a fresh set of Champions and swap out the old plugs anyway, they're cheap enough.

Also, maybe the fuel filter is clogged up and starving the engine of fuel? Again, it's a cheap part that's not hard to change out.

(edit) And, now that I think of it, how's the air filter look?

The fuel filter is in the gas tank so it's not easy to change!

RCP Phx said:

The fuel filter is in the gas tank so it's not easy to change!

Click to expand...

It is? Sorry, didn't realize that the 97-01 models didn't have it hanging on the frame rail underneath like the earlier ones (such as my '92) do.

I stand corrected on the fuel filter.