I’m in the middle of doing a head gasket job(my first one), and opted to replace the seals on the fuel injectors. I ordered the Elring head gasket set from FCP Groton, as well as the Bosch fuel injector seal kit. The description of the head gasket set says it has all the seals/gaskets for the head up, excluding the fuel injector seals. After reading this I decided it was necessary to order the fuel injector seal kit. Everything arrived and I slowly got to work. The head gasket kit came with several items I have no idea what the hell they are for. It seems like the Elring set does indeed come with half of the O rings necessary to reseal the injectors(4). And the Bosch kit comes with the following…

1 protective sleeve (yellow) # 1 280 423 712
3 O-rings (black) # 1 280 210 711
1 support ring (grey) # 1 280 320 052

The instructions in the Bosch Kit are as follows…

1. The old protective sleeve must not be re-moved from injection valves with yellow supporting plate
2. Only use flat seal ring and O-ring (1-item) when a pressure regulator intended for use with o-rings is replaced

So at this point I’m kinda pissed off because I ordered 4 Bosch seal kits at $4.50 each.
And going by the instructions all I need from the kit is the o-ring because my injectors have the yellow support plated, and the head gasket seal kit has half of the o-rings that I need. If anyone knows anything about this can the please post back. Also there seems to be some contradicting information in the FAQ’s as far as cleaning the injectors. In one area it is saying that 12+ volts go to the injector, then Mike Ponte’s direction say only to use 2.4 volts.

Thanks for the responce brad. However the directions say that if your injectors have a yellow supporting plate like mine do not to remove the yellow sleeve. Does anyone know another way to test spray/clean your injectors other then the 10 watt bulb tecnique. I'm thinking I'm just going to hook them back up and power them by turning the key
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Vinny Lacorazza, North West Corner Connecticut

When I did the head gasket on my 940 last year I also replaced the injector seals. I ripped off the yellow protector caps with pliers - they can be hard little buggers to get off. I then used a small screwdriver to pry the old seals off, put a thin smear of vaseline on the new seals and put them on. Then I attached the new protector caps. IIRC I had seals left over but I can use them next time. I don't think I touched the grey rings.

Good Luck
Brad
91 940GL

When I did the head gasket on my 940 last year I also replaced the injector seals. I ripped off the yellow protector caps with pliers - they can be hard little buggers to get off. I then used a small screwdriver to pry the old seals off, put a thin smear of vaseline on the new seals and put them on. Then I attached the new protector caps. IIRC I had seals left over but I can use them next time. I don't think I touched the grey rings.

Good Luck
Brad
91 940GL

When I did the head gasket on my 940 last year I also replaced the injector seals. I ripped off the yellow protector caps with pliers - they can be hard little buggers to get off. I then used a small screwdriver to pry the old seals off, put a thin smear of vaseline on the new seals and put them on. Then I attached the new protector caps. IIRC I had seals left over but I can use them next time. I don't think I touched the grey rings.

Good Luck
Brad
91 940GL

Is there something else you can use other then a 10 watt light bulb, I have never seen one of those.
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Vinny Lacorazza, North West Corner Connecticut

Can't speak to the seal issue since I did mine a long time ago, but the injectors do indeed have +12V applied from the battery via the radio suppression relay, grounding through the ECU on each stroke. There is resistance inside the ECU. Mike suggested using a 10W light bulb to provide external resistance sufficient to limit the current draw through the injector and not burn up the windings. The voltage at the injector is irrelevant: as long as it is sufficient to operate it with frying the windings, then you're fine.