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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, 02:54 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, 03:06 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, 04:49 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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Bruce P.
1988 951 Alpine White, AutoAuthority chip, HRE custom wheels, 10 speaker panels, Schnell short shifter, M030 sways, Koni Sports
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Old 06-11-2017, 07:14 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, 07:09 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, 08:50 AM
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Yes they measure out at 14.5mm.
Old 08-20-2017, 11:10 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, 10:24 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, 02:25 PM
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