[GeorgiaTech335coupe]

Replacing my injectors for the 2nd time today. The first replacement was done under warranty a little over a year ago. The injectors had the updated part #. About 13k miles later, I'm replacing all the injectors again out of my own pocket. Way to make a robust design BMW engineers...

This stemmed from my car misfiring. Initially, it only happend during WOT towards the top of the RPM band in 4th gear. Problem progressively got worse, where it would do it any time I lugged my car and in all gears from 2-6.

[Joshboody]

Sorry to hear... did it fix the problem? Do you know the separate cost for coding the injectors... probably referred to as reprogram in the invoice. What's wearing in the injector.. piezo element?

did you check the misfires codes... all cylinders or select ones?
what mods do you have?

hope these work for you!

[jaymd123]

Are you sure its not the coils? I had misfires that went away by replacing plugs but eventually came back after 10K. Turned out it was the coils but getting new plugs made the symptom go away for a while.

[Joshboody]

to answer your question, I replaced 1 bank due to misfires on start up. This was caused by the injectors leaking when the car sits. Not related to your issues of course.

i find that my car has some very very slight stutters with accelerating before it's completely warmed up... i assume this maybe an injector issue. But no misfires have been recorded yet.

[GeorgiaTech335coupe]

Fully modded w/meth. Checked coils and plugs before replacing injectors since that takes 5 minutes. My friend's shop has a GT1 so not sure what it costs to calibrate them.

First replacement was done by BMW for cold start misfires. They replaced all of bank1, I got misfires again the next day, then they replaced bank 2.

This time around, I initially was only getting misfire cyl 2. Replaced cyl 2 injector, then immediately starting getting misfire cyl 3. Replaced 3, then immediately started getting cyl 1. Replaced 1 and car ran great for about 2 weeks. 2 days ago I started getting misfire cyl 6. 99% sure I will have to replace the entire bank from the previous experience.

On my 2nd set of plugs, when we pulled them they looked fine. Some of my coils are new from when BMW replaced my injectors, don't remember which ones though.

[NiVeDh]

I'm on my 2nd set. Just got them replaced under the recall. Hopefully the misfires are gone. I'm going to go pick the car up now.

Go Georgia Tech!

[dzenno]

What tune are you running currently and how do you know its your injectors for sure?

[GeorgiaTech335coupe]

Originally Posted by dzenno

What tune are you running currently and how do you know its your injectors for sure?

Procede. becuase when I replaced them the problem went away.

Update: only replaced injectors 5 and 6 today. So injector 4 is the last man standing. Injector 5's seal looked pretty beat up, injector 6's seal decided to go on vacation as there was a lot of carbon build up on part of the injector that is outside the cylinder. Hopefully, the misfires don't come back, if they do....#4 is getting replaced.

[dzenno]

Did you update to the latest firmware/maps....if you're a 6AT it may be a procede issue you're seeing as they recently had a fix for it that was misfire under load related

[GeorgiaTech335coupe]

Originally Posted by dzenno

Did you update to the latest firmware/maps....if you're a 6AT it may be a procede issue you're seeing as they recently had a fix for it that was misfire under load related

Haven't updated to V5, but I have the latest beta just been too lazy and wanted to get this issue sorted out first.

I'm MT, but I am aware of the ATs misfiring at high load.

[dzenno]

I'd update it anyway first unless you're misfiring stock...

[GeorgiaTech335coupe]

Originally Posted by dzenno

I'd update it anyway first unless you're misfiring stock...

Injectors have already been replaced so too late now. FWIW, it did misfire on valet as well. More difficult to get the car to misfire and go limp with less boost, but I could still do it. I highly doubt this would've fixed it anyway. The first 3 were done one at a time, with the misfire in that particular cylinder never coming back, so I doubt software update would've fixed it.