Misfiring, where to buy injectors?

[muddeprived]

My stupid as$ 4.0 is misfiring like no tomorrow. I started off with a misfire in cyl 3 when I bought it and it happened every now and then. Now I get misfires randomly in all cylinders. I went wheeling yesterday and the BDS Outback Adventure and I couldn't shut off the jeep on the trail or else it would misfire really bad. I think my injectors are going south. I looked up how much they costs and $60 each!!?? That's gonna costs around $500-$600 just to replace 6 injectors and a fuel rail? WTF That's insane.

Is there any place that sells a package deal of 6 injectors at a lower price or individually cheaper?

I am almost considering selling this p.o.s. because of how unreliable this stupid motor is. Sometimes I wish I stuck with my 2.5L cuz I beat the living hell out of that thing for four years and never a single issue or leak. It was bulletproof.

[brooks_mcclintock]

uh, are we talking about the same 4.0l? Goto a junkyard and pull the injector system and install it, see where it goes. It could be something else.

[2000XJ]

Mudd, don't sell it. All your experiecing (most likely) is the typical vaporizing of fuel in the fuel injector. Here is the TSB for it: http://www.wjjeeps.com/tsb/tsb_wj_1803103.pdf

I experienced this problem with my '00 XJ also when I was wheeling. I did as the TSB instructed, and it helped to prevent it as well. In some extreme situations, it will still happen. What I do to prevent it to the point where it basically doesn't happen at all is that if I'm idling for a while on the trails I'll pop the hood to let hot air out. When I stop for lunch or if I'm guiding and will be out of my vehicle for an extended period of time I put the hood prop up to the first hole (about 12" high instead of fully opening the hood) so that the sun doesn't hit it, but so that everything cools off. I know it's kind of an inconvenience, but it's really not when you know that you won't have to deal with this hastle.

[5-90]

Are you sure it's injectors? Possible misfire causes (in no particular order):

- Failed/failing fuel injector(s)
- Failed/failing spark plug(s)
- Failed/failing distributor cap and/or rotor
- Failed/failing ignition HT lead(s)
- Failed/failing ignition coil
- Failed/failing primary grounds (and you'd be amazed to know how many auto electrical problems I've tracked to shonky grounds in the last thirty years or so...)

You get the idea. To be perfectly honest, I'd check the main grounds first. Not only can they interfere with spark production, but the sensor signals that the ECU uses to gage fuel injection pulses use the ground as a "zero reference" - and if that is not a solid ground, the signals will be invalid (but the ECU won't know that, so it will keep on keepin' on - and screwing up.)

[muddeprived]

Originally Posted by 2000XJ

Mudd, don't sell it. All your experiecing (most likely) is the typical vaporizing of fuel in the fuel injector. Here is the TSB for it: http://www.wjjeeps.com/tsb/tsb_wj_1803103.pdf

I experienced this problem with my '00 XJ also when I was wheeling. I did as the TSB instructed, and it helped to prevent it as well. In some extreme situations, it will still happen. What I do to prevent it to the point where it basically doesn't happen at all is that if I'm idling for a while on the trails I'll pop the hood to let hot air out. When I stop for lunch or if I'm guiding and will be out of my vehicle for an extended period of time I put the hood prop up to the first hole (about 12" high instead of fully opening the hood) so that the sun doesn't hit it, but so that everything cools off. I know it's kind of an inconvenience, but it's really not when you know that you won't have to deal with this hastle.

I was kinda speaking out of anger when i mentioned selling it. It's just been frustrating me the past month. First my rear main starts pouring out oil and i had to do the rear main seal and then the tranny overheats and spits out fluid from the dipstick. Now it's misfiring on and off, leaving me stuck with keeping it running instead of shutting it off and having a misfire when i restart it. I used to pop the hood when I first got it cuz I had the p0303 code every now and then but it became old, having to do that just to try to prevent a problem from appearing. We do alot of stopping on our trails and some of them are long recoveries so i'm wasting gas leavin it running. To me, a good motor is a motor that runs without issues. Mine has alot, so it's not what I consider a good one. I know there are 4.0's that last forever, and my friend has one in his YJ. Not a single issue with his. Mine's just been bad luck. I haven't started my new job yet (maybe this week) so I can't afford to spend much on diagnosing the motor issue so i'm just keeping my fingers crossed that it can get me through a couple weeks of work and have money to fix it.

[5-90]

Feel free to run down the list I posted - most of those items can be checked easily with common tools (usually a DMM...) and ruled out. Check them off the list, and go forth from there.

Fuel injector coils can be tested by checking the coil resistance with an ohmmeter. Then heat them up with a hair dryer and look for an intermittent. Shake them around when they're hot - since that's when a malfunction is most likely to occur.

A similar test can be applied to the ignition coil, for similar reasons.

You get the idea. All of these tests cost you nothing but time, as long as you have a DMM and necessary tools.

[mcatald]

UHHHHHHHH.......I should say selling it should be the farthest thing from your mind. You will get her figured out.

[muddeprived]

Well it's been a good girl lately. No misfires but no long driving trips so I don't expect it to misfire.

I got a dude at a shop down the road who owns a lifted XJ and said he'll help me diagnose the issues at his shop. He has all the tools to do so. I gotta wait till i start my job first, sometime this week, and get some cash.

5-90, i printed out everything you suggested and I will bring it to him so we can work down the list. Thanks to you and everyone else.

[cubanater]

muddprived my heep would misfire it would stall out it did everything in the books. i changed every censor known to man then some....one day little drunk at that, i decided to pop my hood and stare at my pile of disappointment... so i decided for some odd reason to move one of my injector wires... come to find out, on the side i couldnt see both the wires were bare... so i taped it up. since then it has not sputtered, check engine light ran away and runs a million times better... goodluck tell us what fixes it

[JpUseR96]

you need 25 pounder's. "METERED" (very important) multi-port fuel injectors. Believe it or not JC whitney can fix you up!

[Trooper]

The POWER of beer. Even makes the ugly ones hot... which requires ALOT of beer.

[JpUseR96]

Hey Muddperived, how can I locate the TSB's for the jeep listed above?? PLEASE give me a link.

[muddeprived]

Originally Posted by JpUseR96

Hey Muddperived, how can I locate the TSB's for the jeep listed above?? PLEASE give me a link.

Try this:

http://repairpal.com/jeep-cherokee-1996/recalls_and_tsbs

[JpUseR96]

Thank you!!

[Deepwater Jeepin]

Did you ever get the missfire issue sorted out Mud? Was it the fuel in the injectors vaporizing? What did you do? Im having the same issue.

(Thanks Stamp for pointing me to this thread)