Matt Krumwiede

So some quick background: I replaced the cylinder head in my 2001 XJ limited several months ago. I replaced 4 of the 6 injectors with 4 hole injectors(I'm guessing this may have something to do with my problem) I also bypassed my heater core due to a nice little issue with my heater core peeing all over my passenger side floor board

So, several weeks ago before I went out to Ocala to go camping my engine light came on out of nowhere. I had has some rough idle the past few weeks before that. I got the codes read after my camping trip and the code reader said I had multiple misfires. I can hear the injectors from inside my cab and I know the older injectors are noisy but d***. Any ideas or information on where I should look would be greatly appreciated. Thank you

00t444e

Putting all 6 of the same kind of injector would be a start. Then after you do that unhook the battery cable for a few minutes to reset the computer. If you still have problems it could be ignition related so check your plugs and coils.

Matt Krumwiede

Well I had a chance to look under the hood today. The radiator fluid is pretty brown, but I'm guessing it just needs a good flush, because I haven't done one since I changed the head. Also, I bypassed my heater core and it looks like it is slowly leaking coolant onto my valve cover right about the 3-4 cylinder and spark plugs. I am thinking this will be another thing to look at and possibly replace the spark plugs.

extrashaky

Did you replace the remaining injectors so that they're all the same and reset the computer as noted above? I don't know why you would be trying to do anything else before this.

AFTER you do that, if the problem isn't solved, start working the problem systematically.

Check your fuel pressure at the rail. It should be 49.2 psi plus or minus 5 psi.

Clear your codes and pay attention to which ones come back. Sometimes the '00-'01 computer will pitch a tantrum and throw extraneous codes trying to keep the Jeep running. What starts as random misfire can sometimes settle on a particular cylinder, which can help narrow your focus.

If your misfire settles into a single cylinder, swap that cylinder's injector for one that is firing normally and see if the misfire moves. If it does, it's a bad injector.

Borrow a noid light from Auto Zone and check to make sure all your injector plugs are getting a signal.

Check your plugs for any abnormal wear patterns. If your misfire settles into a single cylinder, swap plugs around just like with the injectors.

Check compression. You can also borrow the compression kit from Auto Zone.

There's a bunch of other stuff to try, but start with these tests and come back when you have some results.