G50 VH45 injector O-Rings. What am I doing wrong?

[elwesso]

So as you guys know im working on Ross's green active Q.

It came to me with a rough idle and the injector O rings were leaking. So I replaced them, and I pressure tested it probably 20 times before I buttoned it all back together.

Drove it back and the rough idle is back. I pulled the plenum back off (I got it off in 15 mins, anyone care to try and beat me... ) and pulled the fuel rail so I could see the injectors. The 2 injectors I serviced are now leaking worse than they were before. In retrospect, im lucky the engine didnt hydrolock.

I havent pulled the injectors out year to see whats going on with them but the O rings are definitely bad.

Heres what I did. When I installed them, I doused the injectors and the inside of the fuel rail with WD-40. The O rings are made to handle gasoline, I figure WD cant be worse. I press them in gently and then I screw them down with the cap. I tried pressing down on them and I didnt feel comfortable doing that so I figured it might be better to use the cap and lower them down slowly.

Should I press down on them to get the O rings to seat? I dont want to damage the fragile plastic on the top of the injector which is why I opted the way I did.

ANY HELP IS APPRECIATED. THE CAR IS APART RIGHT NOW!

[Q45tech]

WD40? why not vasoline or a tiny tiny spare of silicone.

[elwesso]

it was all I had really handy, but if you think vaseline will work better than I'll use it.

[ScottJackson]

the upper (big) o-rings or the little lower ones? I always put both rings on the injector and then smear a little vaseline on the o-rings to pop it in place.

congrats on the 15 minute plenum pull. I could do it in that time if I leave out the two little 10mm bolts under the front runners and if that little hose under the throttle body comes off easily. Otherwise, those couple things can easily take more than a half hour.

Also, used O-rings are more difficult to seat than new ones because they seem to expand with age. I use a small piece of wood or screwdriver and light mallet to tap them into the pocket of the fuel rail. Maybe I'm just lucky, but I haven't broken the plastic on one yet. I tap lightly and push down at the same time on the flat area just to the side of the middle metal pole sticking out the top of the injector.

[elwesso]

We're talking about the little ones onthe bottom. Ill try the suggestions listed, thanks a bunch!

[goody90q45]

I feel your pain. I've had two lower o-rings come loose while driving (=hydrolock) and have had the good fortune (lol) of replacing 4 injectors in my 2 years of Q ownership.

Take a look at the fuel rail mating surfaces. The upper o-ring groove can hold a lot of dirt and the lower surface, even though it's submerged in fuel, can hold some dirt also. I used a small lab bottle brush dipped in acetone to clean the lower surface and a split wood tongue depressor for the upper groove. While you're cleaning the upper groove feel for any nicks.

Lube both (new) o-rings up heavy with vaseline (.100" thick) and do the same to the fuel rail mating surfaces. Any excess will dissolve within 30 seconds after the engine fires up. You should be able to push the FI in by hand plenty far enough to get the metal cap on and then screw it in evenly.

All bets are off if your trying to reuse o-rings. At 40psi+ it doesn't take much of a nick or defect to cause a leak. Good luck.

[elwesso]

We got the injectors leaking from deatsch werks I think because the idle has been rough from the get-go. I dont think Ross checked the injectors before he put it in. So, deatsch gave us a free set of O-Rings.

Im gonna try this tomorrow morning after I get back from work, I have to get up at 6AM tomorrow (pretty sure thats before god wakes up). When im used to getting up at about 9am, id rather kick a rusty nail...

[maxnix]

I thought Ross had his done at Deatschwerks?

In my limited esperience, I will never install an injector unless the fuel rail is out of the car. Way to many ways to bungle the job with the rail on the manifold.
Modified by maxnix at 6:46 AM 7/30/2007

[Q451990]

I have to get up at 6AM tomorrow (pretty sure thats before god wakes up). When im used to getting up at about 9am, id rather kick a rusty nail...

Amen brother! Sounds like you need a career in Real Estate... I'm probably the only guy on the block that has his coffee pot timer set for 9:30

Ditto on the vasoline...

Heath

[ScottJackson]

Since I'm a farmer and all, I normally wake up around 10 or 11. All this talk of getting up early reminds me of Lawrence in "Office Space". "yeah, puttin' up the drywall at the new McDonald's"

[AZhitman]

Wes:

NO MORE WD40. Vaseline only.

Also, find a socket that fits perfectly INSIDE the small recess in the top of the injector (I want to say it's an 8mm, but I could be wrong.

Place the socket into the recess, and put a ratchet (or something wide) on the back of it, then press with the heel of your palm - it should POP right into place.

Do NOT try to use the screws and cap to "pull" it down into position, it won't go deep enough.

[99q45t_vl]

Wes, I'm not sure about Vaseline. I had to replace mine about a week ago - had a misfire in #2 cyl. I've used the silicone grease which I found in the plumbing dept at Home Depot. Always use the new o-rings. Push the injector down with a little pressure and feel it pop right into place. Before you do that, if you had gasoline in the cylinder, use the pump to suck it out. Good luck.

[elwesso]

I thought Ross had his done at Deastsch?

In my limited esperience, I will never intall an injector unless the fuel rail is out of the car. Way to many ways to bungle the job with the rail on the manifold.

He did, they were bunged up when they got them from deatsch. Only one ive heard of having this problem so hopefully it wasnt a big deal. Good thing is they offered to either send me new O-Rings or redo the service.

I agree about installing the injectors with the rail undone. getting them out is the tricky part, and with the rail at least unbolted from the plenums you can just pop them out from the bottom, pretty easy.

Greg, thanks for the advice, I will install the injectors today with a healthy dose of vaseline...

[elwesso]

Just to let everyone know, I got it all buttoned back up.. it runs OK, the injectors seem to hold good pressure. Still it idles rough, im guessing that the spark plugs are fouled... Tons of smoke from the unburnt fuel (I ran the car for about 10 mins in this condition while I was trying to charge the AC).

[ScottJackson]

could also be a bad MAF. If it seems to be running way too rich at idle, pinch the fuel feed line with pliers to cut the fuel supply to a trickle as it's running. If it clears up and the idle smooths out, you know it's not spark to blame.

[elwesso]

Ok I took the car for a drive. I performed the italian tuneup and it seems to be pretty good. I cnat make a final verdict because I have to order a couple gaskets so its possible i have some small vacuum leaks.

[sdkhalsa]

Just had some bad injector leakage problems on my 94' G50. My DataScan set-up using the cylinder isolation function indicated two likely places for the leakage. Spark plugs showed some carbon build-up but nothing definite. To double check I had TPI in Tempe test all of the injectors plus install new o-rings -- these 2 1/2 year old injectors tested fine. To be a bit on the safe side, I put in mostly new injectors under the plenum plus two that were less than a year old. Conclusion from TPI was that the o-rings were failing. They also noted lots of failures with Nissan injectors. To summarize, I feel your pain!

[silkysmoothyjud]

adjust idle to 1000 rpm, I got bad injectors from d-works, if I get the time to go out and test the other used 370cc injectors that I have and that I did not get serviced by d-works and if they work Im not going to be happy with d-worse.... said injectors caused a choppy idle, my water pump blew its gasket....I am still out for blood

[maxnix]

adjust idle to 1000 rpm,

Way too high unless you want in town gas mileage to plummet to low teens.

[elwesso]

how did you determine the one you got from deatsch werks were bad?

[silkysmoothyjud]

after I installed them I got serious vibrations after the car warmed up. Smelling a rat, I ordered an OEM one from a local store. With just one installed, the vibration got better, I ordered two more from joe and a botch one (big mistake), but it was too late, my water pump went bad. Ive been messing around with this rail of used injectors I got off e-bay for a while and I got tired of trying to cheap out and just bought new ones. Ive got the ones done by d-works and I have some untouched ones still. I am tempted to test them in spots one and two. But my injector work is done, I caught the water pump before it fried my knock sensors. I will take doing injectors 1 though 4 about ten times as a lesson learned for now, but I'm a little upset about it.....For further clarification, I had used injectors serviced at d-works and they came back bad. I never tested them before they were sent, but they did ohm to speck before and after service.....
Modified by silkysmoothyjud at 9:35 PM 8/22/2007