Can't access the fuel injectors on the M30

[Jazz_89]

Good morning everybody,

I want to measure the resistance on the fuel injectors.
They are visible right under the fuel rail and this long cable box, but I cannot get to the electrical connectors. Should I remove the intake rubber boot first?



Thank you

[genphreak]

Yes. Unless you take it on yourself to do an 'Alpina TB conversion' before removing the injectors, you have to be able to get to them that way.

I use a screwdriver to release the clip on each one, moving front to rear as I pull up (gently) on the plastic wiring enclosure. You really need to be able to access each one.

Before re-installing clean and grease the o-rings- even if you replace them. Over the years they shrink and squash, which means they allow air to leak in on each intake stroke... not good for generating power!

[Jazz_89]

I use a screwdriver to release the clip on each one, moving front to rear as I pull up (gently) on the plastic wiring enclosure. You really need to be able to access each one.

I tried to remove some clips, but I noticed that there are only cables beneath the plastic enclosure. Can I remove the connectors to the injectors from there?
Thank you

[Jazz_89]

And how do I continue from here? I cannot remove this cable box in order to get access to the electrical connectors of the injectors :/

[shogun]

Have you checked the workshop manual already? https://www.bmwtechinfo.com/repair/main/

[Jazz_89]

Have you checked the workshop manual already? https://www.bmwtechinfo.com/repair/main/

I looked there but it doesn't really help. It says to remove the fuel rail but I think I need to depressurize for this...I can see the rubber top of the electrical connectors to the injectors with two wires each, but I cannot unplug the connector itself

[genphreak]

Fuel pressure drops after 20 minutes or so. Just take care when removing a pipe and be ready for fuel to come out (don't smoke, have a jar to catch it and wear glasses, etc.)

The plastic injector harness box normally sits directly on top of the injectors and can come off without doing anything to the fuel rail. It is probably 'well lodged' after the years so resisting your efforts. You lift the rear or front first, unlock each injector plug clip one by one moving to the other end. Just press the metal spring in towards the injector. Some clips may be hard to reach or the clips jammed or broken, perhaps spray with penetrant- and use your fingers or any other implement you can to get a positive result. They will probably come off if you put them under extreme force alone- but try not to do it this way, jic!

If this doesn't sound right, post some pics so we can see what you see! Yours may be different for some reason- and if it is we'll be able to tell you why :-)

[shogun]

http://www.nmia.com/~dgnrg/page_17.htm
maybe these pics help?