Replaced injectors and had a miss for the first 3 starts

[Old-Duckman]

2004, E85, M54 3.0i, 59K, manual.

So I bit the bullet and bought all 6 new fuel injectors. The suspicion from several sources (including member GnomeDoctor...Thanks!) was a leaking injector. So instead of trying to figure out which one was the issue I bought and installed all 6 this morning. Not a bad job, getting the electrical connections off of the old injectors was the most difficult part (broke a small piece of the plastic off one side of the #6 cylinder connector).

When I buttoned everything back up and started the car it had a pretty bad miss. Pushed down on each connection to each injector, all seemed to be tight, I was worried that the small piece I broke had something to do with the issue. Anyway started it 2 more times, same problem...a miss. I have new coils waiting for the time they might need installed but I did not want to put them in now. My old Ducati mechanic told me years ago that when there is a problem always check the last thing you worked on. So I did not want to add the coils to the mix but I did unplug each and re-plugged them.

So I ran a diagnostic with my Foxwell hoping that it would show me what cylinder was having the miss...it did not. Removed the Foxwell and started it up and no miss. Took it for a short ride (in-case it had problems) and it ran fine.

All that to say...any ideas why it was missing at first? Could it have just been something in one of the injectors from the manufacturing process?

I must admit that I am not totally confident that the miss will not redevelop but what can I do but keep my phone and insurance card with me when I am driving.

Any thoughts on what might have happened would be appreciated.

 

[Jfgoldfish]

Did you code the injectors to the ECU?
Not sure if that would cause you miss; that might just have been air in the fuel rail working its way out. They really should be coded though.

 

[AndyBeech]

Did you code the injectors to the ECU?
Not sure if that would cause you miss; that might just have been air in the fuel rail working its way out. They really should be coded though.

No coding required IIRC. Didn't need to on the M anyway there is no option for it.

 

[Jfgoldfish]

No coding required IIRC.

You may very well be correct. There seems to be a lot of conflicting information about it.
I thought all the 6 cylinder engines required injector coding but that might not be the case. I don't have any first hand experience with those particular engines.

 

[Old-Duckman]

Thanks for the replies. I just did a search to see if the M54 needed the injectors coded. I saw no definite statement saying they did or did not need coded. The general thought seemed to be that if the car has direct fuel injection then coding is necessary. I saw a good many articles on coding injectors for an N54 engine.

I'm hoping Jfgoldfish's comment on working air out of the fuel rail was what I experienced. I am taking the car to a BMW inde on 20 July for alignment and will ask them about the coding issue. I'll reply to this thread when I get his answer. I was wondering if something like that was the issue but am not educated enough to know just what might be the cause of what I experienced, thus my original post.

As I noted in my original post, the car ran fine when I took it for the short "shake down" cruise but it was very short, probably 2 miles or so. And, due to the fact that I have new rear tires and one is very obviously out of alignment relative to the other tire I do not want to drive the car until I get it aligned...don't want to unduly wear the new rubber.

Thanks again for the comments.