'96 855R: Where do the injector cushions disappear to?

Post by **MrPc** » 07 Jul 2014, 10:27

I was servicing the PVC system this weekend. (Only got ~30k miles out of URO hoses installled last time...)

When removing the fuel rail, the fuel injector cushion for cylinder 4 was missing. I know I installed one last time I had the fuel rail off, but I couldn't see where it went, figured it must have fallen behind the intake, and I'd find it later after the manifold was off. But of course, later when everthing was off, I couldn't find it. I took a really hard look around the starter and starter solenoid. I had a few spares, so I just put one in.

I reassembled the car, and it started right up, but it threw a code. Looking under the hood, the problem was obvious: a large fuel leak from the injector on cylinder 4, at the o-ring.

I popped the fuel rail off to address the issue. The o-ring was torn, I must have pinched it when installing the rail. And the !@#$ injector cushion was missing again! Shining a light behind the intake didn't reveal anything.

So I put another spare into the fuel rail and went to install it. While tipping the fuel rail into position, I saw the injector cushion for cylinder 4 leap out of the fuel rail, and disappear behind the intake manifold. But of course, I couldn't see nor feel it when I went looking.

I was running low on spares at this point, so I applied a small amount of adhesive to hold the next one into the fuel rail while I installed it. Car started right up, no codes, vacuum in the crankcase.

So my questions:
1) Has anybody seen my fuel injector cushions?
2) Seriously though, it has been my practice when installing the fuel rail, to put the o-rings on the injectors and then bring the rail home. This is what gives the cushions a chance to run for it. Should I be stuffing the o-rings into the rail instead?
3) Does this happen to anybody else?

As a final side note: The last time this happened was about 2 years ago when I replaced my valve stem seals. I found one of them about a month ago when I was replacing my inner tie rods. It was sitting on the subframe under the steering rack...

Post by **Ben850** » 07 Jul 2014, 11:07

I put the injectors in the rail first, which secures the cushions.

Using the complete rail to push the injectors in place.
I have seen a containment piece on the newer fuel rails that would not allow it to be done any other way.

Post by **rspi** » 07 Jul 2014, 14:47

I do NOT remove the rail when doing the PCV job. Not sure why people do. Fuel injectors are delicate, the seals are old, and when things fall off, they are hard to find if they don't roll away.

Post by **abscate** » 07 Jul 2014, 18:09

I was servicing the PVC system this weekend. (Only got ~30k miles out of URO hoses installled last time...)

>> long after the price is forgotten.....

My PVCs are original and 16 years old. I think I will replace with Volvo stuff....

Post by **scot850** » 07 Jul 2014, 23:22

I will never, ever use URO parts again unless there is no option. I ender up removing the intake once after less than 400 miles when the short 'J' hose split in the middle (supplier said they had had 3 other customers with the same problem and now only supply Volvo original pipes), and the second time after about 15k miles to try and cure a constant crank case pressure issue. Found the short stub pipe at the back of the oils separator tank to the block had collapsed internally!

Neil.

Post by **Ben850** » 08 Jul 2014, 04:37

rspi wrote:I do NOT remove the rail when doing the PCV job. Not sure why people do. Fuel injectors are delicate, the seals are old, and when things fall off, they are hard to find if they don't roll away.

I had changed the manifold to a "3 bore throttle body and white injectors, while also running a "5/8 heater hose from the oil trap to the PTC nipple. So the injectors were coming out either way.

I had also changed to yellow injectors on the N/A sedan, so those had to come out as well. I had a method at that point for keeping track of seals.

Post by **jblackburn** » 08 Jul 2014, 07:36

scot850 wrote:I will never, ever use URO parts again unless there is no option. I ender up removing the intake once after less than 400 miles when the short 'J' hose split in the middle (supplier said they had had 3 other customers with the same problem and now only supply Volvo original pipes), and the second time after about 15k miles to try and cure a constant crank case pressure issue. Found the short stub pipe at the back of the oils separator tank to the block had collapsed internally!

Neil.

Ugh, I had the same issues the first go-around. Ended up redoing the whole system with Volvo hoses less than a year down the road because they kept failing and/or falling off.

Post by **rspi** » 08 Jul 2014, 07:40

I learned about the crappy URO parts about 30 days after doing my PCV.

I have replaced several elbows on a few cars since. Just replaced the large end joint to my intake tube about 5 days ago. They really stink.

Post by **MrPc** » 08 Jul 2014, 09:28

Thanks for the comments guys.

Rspi, now that you mention it, it does seem unnecessary to remove the fuel rail. I suppose the reason I removed it the first time was because the tutorial says to do so (and the ipd kit comes with new orings). And the second time around I suppose I removed it because it had become a habit by then...

Also a great suggestion to leave the injectors in the rail instead of the manifold...

The first time I did the pcv, I wasn't aware of the quality of uro parts, and just went with the ipd kit. Lesson learned. Although I didn't take pictures, I found that the only parts that were in really bad shape were the hose assembly from the collector to the PTC (brittle plastic hoses snapped easily), the elbows at the end of same (cracked & leaking vacuum), and the short short hose from the bottom of the collector back into the block (small cracks starting). But the collector, the hose to the cam cover and the hose to the top of the block are still in great shape and went into my box of spares. The collector says Volvo on it, so I guess that kit may have been a mix of genuine & URO parts. I don't recall exactly. In retrospect, the heater hose mod would have addressed everything that required replacement, except for the vac elbow at the manifold.

Post by **dosbricks** » 08 Jul 2014, 21:22

I have to say I'm grateful for the MVS record you folks have provided of your collective experience. When I did my wagon PCV a few weeks ago, I used a kit with OE parts, even those beloved Oetikers. Also left the injector rail on the manifold. So thanks guys, you did not suffer in vain.