Injectors leaking boost

BluEVOIX · Aug 19, 2009, 08:50 PM

Ok, did a boost leak with throttle body side capped and the intercooler pipes where all nice and tight.

Then I did a boost leak check with the whole system connected and found that the injectors, mainly the 3rd injector was leaking pressure. It actually starts leaking really bad after 14 psi. I removed the injector and the rubber ring looked ok visually but I guess I need to replace it.

Any one else have issues with their injectors not holding pressure at the manifold seal?

Any recommendations on where/which injector rubber o-rings to get? The ones that connect to the bottom to the manifold.

Also could the injectors be leaking due to the 2 black spacers that are between fuel rail mounting points being too thick?

BluEVOIX · Aug 19, 2009, 08:55 PM

Found some at streettunedmotorsports

http://www.streettunedmotorsports.co...ator_rings.htm

But I'll check tomorrow if AMS has some in stock so I wont have to wait for shipping.

Man this was probably one of the last places I would have expected to find a leak. Sucks!

sparky · Aug 20, 2009, 03:37 AM

blueEVOIX: Tell me again that your car''s intake tract is somehow interconnected with your fuel rail

AWD_Terror · Aug 20, 2009, 05:35 AM

Quote:

Originally Posted by sparky

blueEVOIX: Tell me again that your car''s intake tract is somehow interconnected with your fuel rail

Your injectors sit in your manifold. Your manifold sees boost/vac
He is talking about the manifold seals that the injectors sit in.

sparky · Aug 20, 2009, 05:43 AM

I guess that I'd better go out to the garage and pop the hood to take a look-see more often. I just can't visualize things anymore. But, you are absolutely right. Thanks for the heads-up!

.....and, Duh!

BluEVOIX · Aug 20, 2009, 06:04 AM

Yes I was referring to the seals that sit between the injector and the intake manifold. They look to be in good condition visually, but do not hold pressure more than 13-14 psi and start leaking a pretty good amount after that.

I just ordered new seals and hopefully they hold up. If not I might shave the spacers found between the fuel rail to manifold connection to squeeze the injectors down to the manifold tighter.

So anyways, if you guys havent already done so, make sure you boost leak check with the throttle body and intake manifold connected. You might find some leaks there too.

AWD_Terror · Aug 20, 2009, 06:16 AM

deff good to do boost leaks every few months. I never realized I had a boost leak and had an enormous one at that
to your orig question, FIC makes these really good tight seals made from some space aged materials. lol.
Id check those out.

BluEVOIX · Aug 20, 2009, 08:20 AM

Quote:

Originally Posted by AWD_Terror

deff good to do boost leaks every few months. I never realized I had a boost leak and had an enormous one at that
to your orig question, FIC makes these really good tight seals made from some space aged materials. lol.
Id check those out.

At the moment I just ordered the stock seals from STM, but I will be getting FIC injectors when its time to upgrade my stockers.

EmeryatSTM · Aug 20, 2009, 08:43 AM

Those are in stock and will go out to you today. This is a very common place to find boost leaks.

-Em

JKD · Aug 20, 2009, 09:42 AM

Those seals should take care of it.

bbyevo8u · Aug 20, 2009, 06:53 PM

how hard is it to change out the seals?

EVO8emUp · Aug 20, 2009, 08:38 PM

unbolt the fuel rail, and lift it out.

NsinEvo8 · Aug 20, 2009, 08:50 PM

Definately fix that, you dont want to start a fire somehow..

BluEVOIX · Aug 20, 2009, 09:57 PM

Quote:

Originally Posted by bbyevo8u

how hard is it to change out the seals?

Its not hard to do at all. There are 2 bolts that hold the fuel rail down to the manifold, and in turn the fuel rail squeezes the injectors against the manifold. All you have to do is remove that bolts, but be care full because there are spacers between the rail and manifold. Then you just lift the fuel rail and it should pull the injectors off the manifold.

You don't even have to disconnect the injectors from the harness. Just replace the seals and pop everything back together.

But one thing I noticed and didnt really like is the fuel rail doesnt seem to apply enough pressure to hold the injectors down. Maybe my seals are very worn thats why, but after replacing them and I find that the injectors are not tightly secured I might shave the spacers slightly to allow more torquing on the rail.

SPECJUNK · Aug 21, 2009, 06:09 AM

How big does a boost leak have to be before it concerns you, if the car makes boost like it should, but there is a 1/16" vacuum leak.................is that really a big concern?

if you look at the manifold vacuum and it is stilll making 17" at idle...what all the alarm for