Lady McCoy

I don't have much of a clue as to what's going on, which is why I joined this forum. Hoping to glean some wisdom and, hopefully, be able to get this Jeep in better shape.

"Inherited" a 2000 Jeep Cherokee 4WD 4.0L 6 cyl from my husband, it belonged to his ex-wife. So far, not seeing any history of upkeep except for the oil change and new tires put on before we shipped it here from Hawaii in October. Jeep currently has just over 120k miles.

I've noticed over the past few weeks that the Jeep has been losing significant power when driving in this fantastic highway traffic here, north of San Diego. CEL came on last week, Pep Boys hooked up the OBDII reader to give me the code which came up as a Cylinder 6 misfire.

I've done some asking around, trying to read up on repair guides that I can find online, even interrogating my brother in Georgia who is primarily a VW guy... but since I am not a mechanic, can't afford one, and my experience working on engines is sorely limited to oil/filter changes, I could use some expertise.

Any suggestions would be greatly appreciated, especially since I'm honestly frightened to open the hood.

mentalbreakdown00

Plan on a tune up of plugs, wires, cap rotor, fuel and air filters more than likely

freegdr

you not leaving a hole lot of room to work with if you are scared to open the hood lol

freegdr

i dont think you have wire or dist cap youve got the coil system on yours so its getting easier all ready have you ever chcnge spark plugs b4

DaddyCat

I like the easy/cost effective path. Check or change the spark plugs first.
I'm using NGK V Power spark plugs @ $2 each and I happy with them.

tjwalker

Good advice here.

You have a coil pack ignition system, so you don't have plug wires, distributor cap or rotor.

So concentrate on things specific to cylinder #6.

#1. New plugs. NGK is a good plug choice for hte 00-01 with the coil pack system.

#2. If new plugs don't help, try swapping a fuel injector from the #6 cylinder to another cylinder and see if the misfire follows. If it does, then you know what fuel injector is bad

#3. Running a compression test on all cylinders is a good idea. 120-150 psi is the target there, with no more than a 30 psi variation between cylinders.

#4. You have a vehicle with a suspect cylinder head. The 0331 head has a known casting defect between cylinders 3-4. The #1 symptom of a cracked 0331 head is "unexplained coolant loss". So keeping CLOSE tabs on the coolant reservoir is your new hobby.

mentalbreakdown00

I didn't pay attention to the year, but yeah move the coil from the last cyl in the back and swap it with another one to see if the miss fire moves cylinders. If it does you need a coil, and might as well change all the plugs.

KD3NE

Her fears may be understandable.

I was not afraid to open the hood on my latest XJ acquistion, once opened it I got scared!




On a serious note ....

Plan on a full tune-up. Rotor / Cap / Wires / Plugs

Oil change with filter.

Air filter.

Maybe changing Rotor / Cap / Wires / Plugs will resolve the misfire.


My story .....

The XJ I just bought started giving me Random Misfires causing the Check Engine Light to come on.

I opened the hood and found a Distributor Cap attached to a broken distributor with a wire tie. Previous owner would have been better off using Duct Tape.

I made a good field repair to the Distributor using a long bolt, some flat washers and a lock nut. Took care of my problem.

While I was into it at that level I checked the distributor shop for excessive wear and have a new distributor to install.

freegdr

http://www.4x4xplor.com/sparkplug.htmlthis should help in the plug changing it from a different stlye jeep but the plug changing is the same

lfhoward

I have a 2000 also, and changing the plugs isn't that bad. You have to take off the ignition coil pack, which is a long black rectangular piece of equipment bolted to the passengers side of the engine. It snaps over the tops of all 6 of your spark plugs at once in the 2000 model year, so you can't swap ignition coils front to back. There is an electrical connector on the coil pack that's next to the firewall that you'll need to unhook before you can take it out of the engine bay. The connector has a red plastic clip that slides sideways before it will disengage. Once you have the coil pack off and out of the way, you will be able to see all your spark plugs, and changing them is just like on any other XJ. Good luck with the job!

DaddyCat

nice write up freegdr but so no one is confused ignore steps 1 and 2 when doing a cherokee plug change. Our air intake is not on the spark plug side like the TJ (97-2006 Wrangler) shown in the article.

freegdr

i searched like 20 minutes to make it as simple as possible and the damsel in distress has left lol

DaddyCat

you did good, best article I'v seen. I just wanted to point out what was different.

lfhoward

Agreed. Sweet write up! Thanks for that.

Lady McCoy

Can't thank you all enough for this wealth of knowledge and insight. I plan to brave the engine this weekend to see what my inexperienced self can accomplish.

In looking up all that has been mentioned here, I have found that the coil packs have given me some sticker shock. Wow. The better brands, I guess I understand, this is pretty damn important equipment (but what isn't?). I did happen to come across an anomoly in the prices though... Crown Automotive makes a coil pack for only ~$30 and claims to be a line solely dedicated to Jeep. Is this worth trusting?

Thank you again, for the words of wisdom and suggestions... Feel free to dumb it all down for me, I'm almost the stereotypical female when it comes to car repairs. Almost. ;p