sucking air around fuel injectors

[porcupine73]

Hi all, finished timing belt, water pump, and oil pump replacement, and fuel injector removal, servicing, and reinstallation finally. After first startup, I started hearing a goodly sucking sound with the hood up. So I used my trusty mechanics stethescope (which I had never used before but was invaluable; very easy to find exact source of sound) and it was right where an injector goes into the manifold there. I used all new OE o-rings and stuff when reinstalling the injectors.

 

So I already had everything completely reassambled, so I figured, ah why not and pasted a goodly amount of ultra grey RTV around the injector/manifold interface with a detail brush. Let is harden overnight, fired it up, sound gone. Now I realize this isn't the optimal solution but I was wondering what you guys thought of it....

[svxpert]

<<so I figured, ah why not and pasted a goodly amount of ultra grey RTV around the injector/manifold interface with a detail brush.>>

 

well.... i would have removed the injector(s) that were leaking air and checked for problems. maybe you forgot/double uped a gasket. then re-installed them. what was the reason that you removed them in the first place?

[ferret]

I must agree..and RTV is not the best choice of sealant for any passages that are used for the combustion mixture. It's fumes will poison the oxygen sensor leading to an early end of life.

 

There are warnings all over GM , Mopar and Toyota service manuals about avoiding RTV ANYWHERE in their engines as even sealing and oil pan with it can inject the fumes in the oil and the PVC system will then inject it into the intake....burn in the cylinders and get to the sensor that way.

 

Agreed it is an easy fix, but i would personally take it all apart and fit it back together properly, especially after paying for new seals.

[porcupine73]

Thanks for the info guys. Now I'm a little worried about the O2 sensor taking a hit, but ah nothing I can do about that now, they're relatively cheap anyway since they had a recall on them for my vehicle.

 

Anywho, I removed them to send them to witchhunterperformance for cleaning and stuff; probably didn't really need it but I just couldn't resist trying it. I don't really know what happened on the reinstall; I know I had the o-rings on there. At least it isn't leaking fuel! That would be much worse. The only thing I can think is it was a little tight fit cramming the things back into the holes on the intake or whatever that is they go into, maybe it ripped or something the o-ring. Actually the two cylinders I noticed the injectors sucking air on were the two closest to the radiator.

 

So anyway maybe I'll rip it apart again later. This vehicle was down for it's 105k turnaround since July 4 and the insepction was 3 months overdue so I was just happy to get it back on the road again and I forgot how much fun this '00OBW is to drive. We just got our first snowfall here in Buffalo today and a pretty fierce one at that and this vehicle showed it's colors.

[HondaH8er]

Maybe you just needed to puch the injectors in a little more? Just a shot in the dark, I've never removed/reinstalled my injectors, so I don't know how it is to do it.

[OB99W]

[...]I've never removed/reinstalled my injectors, so I don't know how it is to do it.

Some general info:

http://endwrench.com/images/pdfs/ProperInsideEWFall05.pdf

[porcupine73]

Good point HondaH8er, that is entirely possible. Thanks for that article 99OBW, that is pretty much the procedure I followed, some of the things in that article I think apply to turbo models, like the screws that hold the injectors in place. I'm kind of surprised the article didn't say to replace the o-rings.