Injector Seals
Thread Starter
CF Veteran
Joined: Nov 2011
Posts: 2,381
Likes: 6
From: SoCal
Year: 1989
Model: Cherokee
Engine: 4.0
While working on my NSS tonight I noticed the odor of gasoline in the engine bay. I took a closer look at the injectors and saw that one of them (#4) was wet (the ignition was in the on position but the engine wasn't running so the rail was under pressure). I've recalled reading here that leaky injector seals are a fairly common problem with XJs but I also recalled seeing a receipt given to me by the previous owner for their replacement. I found the receipt and they were replaced on January 3rd of this year. According to the invoice, she was charged (after her 10% "senior discount") $360.51 labor and $22.50 for the seals, seems like they shouldn't be leaking already. The mileage at the time of replacement was 104,206 and current mileage is 106,961. Seems fishy to me.
Should I approach the shop or just replace them again?
Should I approach the shop or just replace them again?
Junior Member
Joined: Oct 2011
Posts: 54
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From: Spokane, WA
Year: 1987
Model: Cherokee
Engine: 4.0 I6
I may be incorrect on this but is there not also a possibility that the leak is in the injector body itself and not the the typical 0-ring problem? I recall reading something about it on another thread talking about swapping over to more modern injectors.
Senior Member
Joined: Oct 2011
Posts: 731
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From: St. Albert
Year: 1989
Model: Cherokee
Engine: 4.0L I6
Take a look at where they are leaking from. I had the exact same thing happen on my 89', and thinking (hoping) that it was a seal, i replaced the seals, only to find that it was in fact the injector body itself was leaking. So I went to the stealership to replace the one. Once installed, wouldnt ya know it, another 2 were leaking. (they were just old and brittle). So I went with a set of the Five-0 motosports Bosch's that was not too much more than one of them from the dealership. Just make sure to lube up the seals before installing. So theres a story that you can hopefully relate to...
Best of luck!
Evan
Best of luck!
Evan
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
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From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Good point. I falsely assumed the OP knew for sure where the leak is coming from. Absolutely, this vintage of injectors is prone to leakage at the body itself.
You can get a set of upgraded injectors with new o-rings from www.precisionautoinjectors.com for about $100.
You can get a set of upgraded injectors with new o-rings from www.precisionautoinjectors.com for about $100.
Thread Starter
CF Veteran
Joined: Nov 2011
Posts: 2,381
Likes: 6
From: SoCal
Year: 1989
Model: Cherokee
Engine: 4.0
Yep, it looks like the body. It's leaking where the plastic connector meets the metal cylinder, either do to age or it may have been pried on a little when they replaced the seals, I would imagine it's hard not to disturb that junction when pulling the injectors. Interestingly, I turned the body about 10º while I was inspecting and the leak has stopped. I know it's only temporary but hopefully it will keep me going long enough to find a 4.6L Mustang GT in a junk yard somewhere. In the mean time, I'll keep an eye and nose on it and I have a 1.5G extinguisher in the car, just in case.
Does anyone know what I'll need to pull the Ford injectors? This is embarrassing but, I've never been to a junk yard before.
Does anyone know what I'll need to pull the Ford injectors? This is embarrassing but, I've never been to a junk yard before.
Last edited by F1Addict; Dec 11, 2011 at 03:32 PM.
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I would look for a set ofthe neon injectors over the Ford's. After running both, i prefer the neons. #703's for 87-98 xj's; #784's for 99-01 xj's. Not sure what all you need for the fords, but for the neons you need a 13mm socket and ratchet and a small flat tip screwdriver.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,577
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Or, just contact www.precisionautoinjectors.com and get a set of 6 injectors, flow matched ,with new seals delivered to your door, with no guesswork for about $100.
CF Veteran
Joined: Oct 2011
Posts: 4,440
Likes: 3
From: Seal Beach, CA
Year: 1996
Model: Cherokee
Engine: 4.0 HO Straight Six
I second getting neon injectors. They're cheap on here (check out the for sale section) and will give you better throttle response and a smoother idle. Depending on your year, you could need a fuel line quick disconnect tool to get the fuel rail out.
Thread Starter
CF Veteran
Joined: Nov 2011
Posts: 2,381
Likes: 6
From: SoCal
Year: 1989
Model: Cherokee
Engine: 4.0
Alright, I'll shoot for the Neon #703s. I've got an '89 XJ 4.0L, so those should do and a 13mm socket and little screw driver are easy enough, I'm sure I'll figure it out when I find [two] Neons. Or, I might just look for them in the For Sale forum and keep my virginity. I'm pretty sure that won't last long, though.
Thanks again for all your help. I'm off to find a short in my reverse lights
Thanks again for all your help. I'm off to find a short in my reverse lights
Thread Starter
CF Veteran
Joined: Nov 2011
Posts: 2,381
Likes: 6
From: SoCal
Year: 1989
Model: Cherokee
Engine: 4.0
...and if they are an EV6 type connector (I need EV1 on my RENIX) what are my options for direct replacement? Christmas is a week away and I can't afford injectors (~$10 each from JY) and EV6-EV1 conversion kits (~$10 each from internet) and rebuild kits (~$20 from my local parts store). I don't care about performance or fuel economy at this point, I just want to NOT have fuel leaking all over the exhaust manifold.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,577
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
www.precisionautoinjectors.com. About $100 shipped to your door, flow-matched, 4-disc, the proper ones with the right connectors, and new-o-rings.
Senior Member
Joined: Apr 2011
Posts: 858
Likes: 0
From: parker, co
Year: 1996
Model: Cherokee
Engine: 4.0 HO
I just put 703s into mine and it's prob the easiest swap possible. Bought em from the forum. Just keep your eyes open in the for sale section and buy em. Usually $45-70.


