background: 89 Jeep Cherokee Laredo all stock parts; injectors have been replaced by previous owner but i'm not sure how long ago it was. A Few weeks ago as I was warming it up in the early morning I smelled the unmistakable richness of fuel. I looked underneath and it was just pouring out underneath the engine on the driver's side. Shut it down and got back to it when I came home. No leak....not for another week or so when the temp got to below freezing (since then it's been like clockwork with the temp conditions) did it leak again but this time I was waiting for it. Pouring out of either the 1st or 2nd injector and was pooling onto the manifold groove there and dripping down to the ground (pic#1). couldn't nail it down to which one cause it's dark and didn't have all the time in the world to get an emergency ride to work but I did remember to note it spurting out of #1.


So I took it to my garage and they determined it was the O-rings and set about replacing all of them upper and lower. They showed the old ones to me, cracked and split so I figured that solved it. A day later after I got it back, the temp went below freezing and sure enough the next day same leak same spot. Took it back, they couldn't get it to leak (was over 40 outside all week) and weren't gonna start charging me for stuff they don't know I'll need...even though they charged me for something that didn't fix it but did need to be done anyway. Now, after searching online and finding and joining this forum I've decided I have enough info along with my neighbor's garage to start doing things myself so here I am.

Fired her up this morning and now low and behold it's coming out of the 3rd injector (pic 2). After seeing how this fuel rail is connected and understanding that the only thing holding these injectors is the pressure from the attached rail I'm thinking as it gets colder out the plastic pieces on the injector or the clips must contract to a degree that it causes a leak. Fuel will seep out even when I just turn the key to engage the fuel pump. Don't know but I'm picking up injectors today and replacing 2 of them. I've read about the whole neon upgrade thing but after what I just shelled out for o-rings, muffler, and exhaust pipe (previous month for inspection and ya they were bad lol) I'm not really looking to go all nuts and I'm mad at myself for not getting to this site sooner (btw $25 for this site is a pittance when compared to garage labor cost). National has the injectors for $35 a pop so I'm good there. Wondering if anybody else has had such a conditional fuel injector leak like this one. It would be easy if it was normal and just leaked all the time. For now replacing as I go and learning more everyday. I'll post more as it comes to pass.

 

I got ALL SIX of my injectors for $60. Shop around dude! My injectors died the same death. DO ALL SIX. Trust me. Your looking at cascade failure if you don't.

 

A friend of mine has had the same issue with his 88 XJ, he ended up replacing the rail to solve the problem.

 

Wow, never heard of that...must have been pulled too hard. Gotta be gentle when pulling these apart as well as reassembling...but op's problem is the body seals, not the rail. DO THEM ALL, with all new orings, AND fuel line disconnect seals. PM me if you have any ?'s, I just did this on my 90!

 

www.precisionautoinjectors.com. Price is for a set of 6. Keep in mind that your original injectors were prone to leaking from the body at a crimp. That coulda been the issue all along.

 

Thanks for the link, The previous owner did have them replaced with Bendix Deka injectors, don't know when but when I looked them up I found a page that lists them as problem injectors: http://www.witchhunter.com/probleminj1.php4
pretty much says what you say.

As I just had the o-rings and seals replaced the only other solution is to replace the injectors.

 

Oh I am doing my due diligence now, thanks for the response or I would be paying waaay too much. Plus...get this....National Auto sent me two different injectors. One was the right one (ford 939) and the other was way too long on both ends and just loose in the box, no plastic bag or protective covers on either end of the injector. Like someone just stuck it in the box.

 

I'm having issues with my 90 as well. Unfortunately my mileage shot up to nearly 20 on the trip where I picked up these 703's. Haven't installed them yet.

https://www.cherokeeforum.com/f2/pul...-right-122194/

 

gonna take back the two I bought locally and get the set from precision and see how it goes. Thanks for the looksee guys it all helps.

 

Sometimes it's just the injector itself or as mentioned the fuel rail. One time I swapped out a rebuilt set of injectors in my XJ with new o-rings and the 3rd one back was leaking at the top. I figured I must have cut or nicked the o-ring installing them (ALWAYS lubricate the o-rings) so I took it apart and tried again with a new o-ring. Did it 3 times and it kept leaking. Finally just tossed the injector up into the woods and put different ones in.

 

The fuel injector body is a two piece design. The injector is literally pressed togeter as a two piece unit. Over a single piece machined body. From what I saw in the photos. This is a typical two piece injector body leak. Sorry to say but you need to replace the injectors.

 

Welp, I replaced the injectors I got from precisionautoinjectors.com (thanks cruiser u saved me a lot of $$) and it was the problem like Norsk said it was an injector body leak for 4 of them but only 2 were spewing it out. Accidently broke my MAP sensor vacuum tube and replaced it with 1/8 hard tubing from autozone and now everything works like a charm.

Thanks everyone who chimed in you all helped. Great forum!!

 

Glad to hear it!!

 

Think about it - the O rings don't seal fuel in, there's no liquid fuel even near them. They seal outside air from getting in.


If it leaks fuel, the body of the injector is cracked - no fixing that, just replace.

 

i would say two of the three seal, the one at the manifold does as you say, and seals against vacuum.