Stupidest Problem In the World

[Barneymac]

Hi all

2008 E93 325i

Fitted 6 new injectors on Sunday, all seemed well for 15 - 30mins into the test drive then all of a sudden started getting misfires. It was all over sometimes just one but was up to 4 on different cylinders at one point. Got all the panelling back off and checked it out and discovered that the electrical connector or all 6 injectors hadn’t engaged with the little clip supposed to hold it in place. My guess is they had been shaking around with the engine vibrations. Checked the old injectors and connectors fit perfectly but not on replacements. It’s like the connector is too long / socket too shallow.

Anyone come across this before? Any ideas what I can do about it? Of all the things that could have gone wrong with the injector change I was not expecting this and am a bit stumped. Suggestions welcome

[bmwmike]

bizarre!

Brand new index 11 injectors from bmw dealer or elsewhere? might be worth checking realoem for your chassis number and see if the loom to the injectors changed at any point. First ive heard of this though.

[g3org3y]

Definitely the correct parts?

Any photos?

[bmwmike]

wonder if they are n54 or n63 injectors...

[Barneymac]

bmwmike said:

bizarre!

Brand new index 11 injectors from bmw dealer or elsewhere? might be worth checking realoem for your chassis number and see if the loom to the injectors changed at any point. First ive heard of this though.

Sorry should have mentioned, they are “re-manufactured” index 11’s from DieselFix Neuss in Germany. The ones that came off were index 9

[Barneymac]

g3org3y said:

Definitely the correct parts?

Any photos?

Definitely, part number the same, only difference is the index number. Pic below, not the best will see if I can get a better one when it stops raining

[Barneymac]

I did a depth measurement with a Vernier today and the sockets on the “new” injectors are a good 0.75mm shallower than the ones on the old injectors.

[bmwmike]

the bodies of the injectors look black - have they been painted? Could the paint be inside the connector base making it shallower?

[Barneymac]

bmwmike said:

the bodies of the injectors look black - have they been painted? Could the paint be inside the connector base making it shallower?

That looks like a really good shout. If that’s the case I bet it’s all over the contacts as well. Will check next time I have daylight and post the result

[bearman68]

Occasionally if we have this problem - and it occurs quite frequently with various sensors etc, we grind a bit of length off 1 of the mating parts.
The little rubber seal causes issues sometimes as well, so a squirt of brake cleaner immediately before assembly will temporarily lubricate the rubber to allow easier assembly.

[Barneymac]

bmwmike said:

the bodies of the injectors look black - have they been painted? Could the paint be inside the connector base making it shallower?

Looks like you are right, first pic is inside the connector on one of the old injectors you can see the bottom and the terminals sticking up with moulded plates underneath. In the “re-manufactured” ones there is some sort of coating in the bottom that looks to have pooled around the bottom of the terminals as well probably adding to the issue. Can’t decide if the terminals themselves are coated or if it’s just that the connector not being able to sit fully down is what causes the misfires.

[Barneymac]

[bmwmike]

That sucks! id be asking for a refund rather than some bodge like grinding down your loom connectors but your call obvs. Wonder why they paint them. Its not like they can pull them apart and refurb them.

BTW word of caution but the injectors can stick in one position if the electrical supply is interupted. Not good if it stick open with a 200 bar fuel supply.

[Barneymac]

I’ve been in touch with DieselFix Neuss about the problem and they have already said that I can return them for a full refund plus they’ll cover the postage. It’s a daft problem to have but they are doing the right thing about it. I have asked them if they know what it is and how to remove it (maybe it’s a coating they put on which is normally thin but something went wrong) but thinking I’ll just return them anyway as have lost confidence in them. Local dealer will put some new seals on my old injectors for me for the bargain price of £90 so will reset everything back to as it was.

[RUSSELLM]

Paint aside... I notice the Grey connector has a keyway. I can’t see it on the Black one.