I'm presently in the middle of replacing my intake manifold gasket, I have the manifold back together, however I still have the injectors to put back in.

I have noticed that on the injector ends that point into the manifold/engine, there is a round plastic 'cap' which appears to clip on to the injector end. I don't really know what these are for, as they leave a large hole on the injector end, however I've noticed that this cap on cylinder 6 injector has cracked.

Are these necessary to retain on the car? Are they supplied as a replacement with the lower O seal? I should renew all the O seals while they are out. I just don't know whether to worry about this plastic part or not.

Thanks

There is an injector seal kit which should contain these little plastic caps. It's made by Bosch, and can be bought from a Volvo dealer; Volvo P/N: 1346393.

I have replaced these before, but I didn't buy the kits fro Volvo, but from diyautoparts.com. You can go to that site and plug in year/make/model info, then look in Engine->Fuel Injection, and find the seal kit. They have a nice picture of the parts. I remember the little yellow caps, but I couldn't remember if they were included in the kit or not. It looks like they are.

I also seem to recall that it contains an extra part or two per kit. I don't think the grey plastic ring applies to the Volvo injector configuration.

You'll need one kit per injector @ ~$6 ea.

You'll also one 'pancake washer per injector. These go between the upper end of the injector and the c-bore in the fuel rail. You MUST have these or you'll have leaks and have to take the thing off again. Another ~$1.50 ea.

You might as well also get the sealing rings that go in the c-bores on the intake manif. There are different versions show w/ & w/out EGR.

You should also get the sealing o-rings for the fuel pressure pipes at the fuel rail. I think there are just two of these; one for supply & one for return.