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Injector leaks

I know I have been dominating the forum with my rolling 85.5 wreck and the aforementioned miss.

So I thought it would be good to check out the fuel system with pressure and leakdown tests, and it passed with flying colors.

However the injector bodies have been wet with fuel on two cylinders right after startup.

Has anyone seen this before?


I have been keeping an eye on this for a few weeks now, and as the car warms up the wetness goes away. I have already replaced one injector with another used one, thinking the body was compromised but the same injector is one of the ones leaking.
Old 06-10-2017, 01:54 PM
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My experience is with '87 NA.

Thoughts:

How does your fuel efficiency compare?

Did you replace parts/clean injectors?

I saw a wet spot on some of mine that went away. I used Dow high vacuum silicone grease to seal them....

Never set up that ATF experiment - remember? Hopefully not!

HTH?
Old 06-10-2017, 02:06 PM
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i would be inclined to inspect the fuel rail.
the 85.5+ rails are prone to cracking where the mounting brackets are brazed to the rail tube.
Old 06-10-2017, 03:49 PM
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+1 on the fuel rail. Mine had a hairline crack at the rear brazing.

Good Luck,
Bruce
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Old 06-11-2017, 06:14 PM
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I think it is fuel gurgling up from the base of the injector getting by the o-ring seal when cold. They are fairly new o-rings but when I pulled the fuel rail to have a closer look there are small cracks in the o-rings like they are dried out. Maybe there is a better type out there or I did something wrong on the install...
Old 08-20-2017, 06:09 AM
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double check what size of o ring you used - i want to say 944s take a 14.5mm o ring for the 14mm hole, but there are also 14mm injector o ring kits out there which won't seal right.

i like to lightly coat the oring in oil before installation, too.
Old 08-20-2017, 07:50 AM
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Yes they measure out at 14.5mm.
Old 08-20-2017, 10:10 AM
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Okay back to this problem for me. With fuel gurgling up around number 2 injector when idling, I removed the rail and changed the orings on #2, same problem. Switch injector 1 and 2 and problem moves to injector 1. Replace injector 1 with a spare and all new o-rings, same problem.

Even when I jumper the fuel pump fuel sprays out around number 1 injector.

Banging my head on fender at this point.
Old 10-30-2017, 09:24 AM
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Problem resolved, bad injectors... Turns out I had not one bad leaking injector but two. The third injector worked without leaking.
Old 10-30-2017, 01:25 PM
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So I had another injector start leaking and fuel was spraying up around where the injector goes in to the intake. Here is a picture of where the injector was leaking, around where the metal tip mates with the body.

So far three injectors have started leaking at this point. I can only think they were stressed when I removed and installed them due to hard o-rings.

Has anyone seen this before? Do the rebuilt motronic injectors Pelican sells have the same seam in the metal where the pieces mate?

Old 12-09-2017, 05:15 AM
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When you're installing the injectors, are you installing them into the fuel rail first and then into the intake? Are they seating right into the intake holes? Does the rail seat all the way down before installing the bolts?

If this were my car, I would look at the intake and make sure the surface of the intake doesn't have burrs on it or is causing some other kind of problem with the injectors rings sealing correctly (like leftover material from a previous o-ring). That can also cause problems with the fuel rail seating all the way down and then having to use the bolts on the rail to draw the injectors into seating (which should never be done). If they are being forced into the intake by the bolts, that can cause undo stress on the injectors that could lead to problems later.

If all else fails, I'd get a new intake and a good used set of injectors and I suspect that would solve most, if not all, of your problems.
Old 12-09-2017, 06:38 AM
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I think too much force was used removing and installing them due to hard o-rings, and they separated at the seam. The metal is actually loose on one of the bad injectors.

What is the proper sequence to install these injectors? Install to intake first or to fuel rail first?

Last edited by djnolan; 12-09-2017 at 07:56 AM..
Old 12-09-2017, 07:53 AM
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OKINJECTORS--Gasoline and Diesel Injector Cleaning, Rebuild, Overhaul, and Testing Services | my-website

Don't mess around any longer. Seen too many ALFA's on the web burnt because of gas leaks that weren't addressed.
People blame Ethanol, but I never had a problem. Some of these rubber lines are over 30 years old. They look good on the outside, but are brittle on the inside.

I send these guys my whole rail and it always come back perfect.
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Old 12-09-2017, 08:00 AM
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Well there was a break in the winter weather so I installed a new set of injectors from FleaBay paid a total of $150 including seals. It now runs smooth even when the weather is cold.

Conclusion: The injectors were not only leaking as shown, but worn out and not pulsing correctly.

I greased everything with superlube grease and everything went together nice and smooth
Old 01-24-2018, 03:03 PM
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Quote:
Originally Posted by djnolan View Post
Well there was a break in the winter weather so I installed a new set of injectors from FleaBay paid a total of $150 including seals. It now runs smooth even when the weather is cold.

Conclusion: The injectors were not only leaking as shown, but worn out and not pulsing correctly.

I greased everything with superlube grease and everything went together nice and smooth
Fleabay? Lol
Old 01-24-2018, 03:55 PM
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