1m Missfire that BMW can't fix

[BarleyE92]

Good luck. I've had two new sets of injectors, and each time the misfire came back about a mile later. Extremely frustrating.

[1&done]

Did you upgrade to the newer injectors?

[BarleyE92]

Update: BMW have the block apart. They're investigating the cylinder head. No major breakthroughs yet.

[BarleyE92]

New cylinder head ordered, BMW HQ have identified that as the issue.

[bdaddylo]

Interesting. Did they not provide any other details?

[nachob]

Originally Posted by bdaddylo

Interesting. Did they not provide any other details?

I hope so but the MO is to keep replacing parts until it's fixed. Lower end next then short-block.... : (


Sorry OP. You have scared all of us and we share your pain!

[goodboy1451]

Wouldn't it be easier for BMW to drop in a whole new engine for you and then ship the problematic one back to germany for analysis.

[Jet Mech]

Originally Posted by goodboy1451

Wouldn't it be easier for BMW to drop in a whole new engine for you and then ship the problematic one back to germany for analysis.

That's what I was thinking also.

[MinusS50]

Misfire is calculated throug the crank sensor it is quite strange they did look at the target wheel / sensoe position.

For problem in the field ( i spoke in general because i never have work for BLW)there a tree of checks to run so they have to do it step by step hence the long delay.

But i found quite strange they did not look at your piston when the head if off

I hope you get round that

[Ba7raini]

Could the low pressure fuel pump be causing this? Had the same problem but on low quality fuel, changing all you mentioned and actually tuning it sorted it out

[BarleyE92]

So, there's an update: While the head was off the car at BMW HQ they found a broken wire in part of the loom that wasn't changed in a previous step. Hey presto - the car no longer misfires! The car has received thousands upon thousands of pounds in new parts, and it seems it was a tiny issue, but hard to find.

They have taken it on three test drives since this, and all three have been good. They were able to reproduce the issue at will before. I'm due to pick the car up later today, so will update again after that. I'm as excited as the day i picked the car up initially, which was 4 months ago. it's been with BMW for the last 2 months!

[Mark 1M]

Originally Posted by BarleyE92

So, there's an update: While the head was off the car at BMW HQ they found a broken wire in part of the loom that wasn't changed in a previous step. Hey presto - the car no longer misfires! The car has received thousands upon thousands of pounds in new parts, and it seems it was a tiny issue, but hard to find.

They have taken it on three test drives since this, and all three have been good. They were able to reproduce the issue at will before. I'm due to pick the car up later today, so will update again after that. I'm as excited as the day i picked the car up initially, which was 4 months ago. it's been with BMW for the last 2 months!

Enjoy

Try and find out where the wire was broken it would be good to know for future ref.

[eeghie]

Originally Posted by BarleyE92

So, there's an update: While the head was off the car at BMW HQ they found a broken wire in part of the loom that wasn't changed in a previous step. Hey presto - the car no longer misfires! The car has received thousands upon thousands of pounds in new parts, and it seems it was a tiny issue, but hard to find.

They have taken it on three test drives since this, and all three have been good. They were able to reproduce the issue at will before. I'm due to pick the car up later today, so will update again after that. I'm as excited as the day i picked the car up initially, which was 4 months ago. it's been with BMW for the last 2 months!

After all, that is excellent news.

Same question as @Mark 1M: In the name of community knowledge growth, could I trouble you to ask the which wire exactly was broken (knock sensor signal, or ...). I had suspected your problem is within the analogue realm and still kind of keen to confirm (or dis-confirm) that. Either name of the signal going through or the indication of this wire connecting module X to module/sensor Y with color Z.

[nachob]

Originally Posted by Mark 1M

Enjoy

Try and find out where the wire was broken it would be good to know for future ref.

Yes, please document which wire it was for future reference as our cars are out of warranty. The other question is how did it break? Usually someone has to pull on it. The cars are too new to be disintegrating yet.

Thanks and congrats!

[BarleyE92]

So far so good. the car feels great again! I haven't got any clarity yet on the wiring in question. I think it'll take a few miles before i feel comfortable driving the car again. At the moment i feel it could go wrong at any minute. Fingers crossed.

[BarleyE92]

2nd update: took the car for a nice long 'enthusiastic' drive last night and it was faultless. Absolutely brilliant. Over the moon to have the 1 back!

(awaiting clarity on the offending wire/loom)

[RS375]

Good news fella, time to finally enjoy the car.

As others have said, feedback if possible on the wiring fault would be great.

[nachob]

Originally Posted by BarleyE92

2nd update: took the car for a nice long 'enthusiastic' drive last night and it was faultless. Absolutely brilliant. Over the moon to have the 1 back!

(awaiting clarity on the offending wire/loom)

They are trying to figure a face saving way to say that a tech pulled it off and that caused all your grief! : )

[Isaacata]

Hey, I have been having the same issue your describing this past couple weeks or so of driving. Took a video of how the car acts once the engine light comes on, happens under full throttle past 4k rpm i get these small consecutive farts and if i keep pushing this happens. Car idles deeper and sounds like a subaru also shakes from side to side when under a little throttle. https://www.amazon.com/clouddrive/sh...hare_link_copy

This video is a little harder to hear but its the same thing just driving slowly, you can tell the car burbles a lot more and sounds like a subaru.

https://www.amazon.com/clouddrive/sh...hare_link_copy

This last video is when it happened on the freeway and i kept driving car. It had happened before on the freeway and went away after 10 min of driving. This time car cut complete power, no throttle and idled very rough had to coast down to a gas station.

https://www.amazon.com/clouddrive/sh...hare_link_copy

What's weird is when i turned it off and then back on the car was fine and drove normal. Car has been at the dealer for the weekend and they said two codes were given one was cylinder 1 misfire second was an issue with the dme. They cleared the codes and everything was running "good" again. Went to go pick up the car drove maybe 2 miles and back to the same issue, not the very rough idle though. Returned the next day and today get a call saying its coil pack and spark plugs. I am betting the issue is not that and will let them know about your fix.

[BarleyE92]

Mine never made an idle sound like that. the missfire occoured under WOT leading to a form of limp mode and stuttery power train.

I wish you all the best. I completely understand the frustration. My car went to bmw almost 10 times before it was fixed.

[ShocknAwe]

Honestly, the symptoms described are typical of what happens if you push a N54 past the initial misfire. Limp and rough throttle.

It's the cause of the misfire that's at question here. It IS typically a coil or plug. This wiring fix is probably extremely rare.

[Dackelone]

Originally Posted by Isaacata

Hey, I have been having the same issue your describing this past couple weeks or so of driving. Took a video of how the car acts once the engine light comes on, happens under full throttle past 4k rpm i get these small consecutive farts and if i keep pushing this happens. Car idles deeper and sounds like a subaru also shakes from side to side when under a little throttle. https://www.amazon.com/clouddrive/sh...hare_link_copy

This video is a little harder to hear but its the same thing just driving slowly, you can tell the car burbles a lot more and sounds like a subaru.

https://www.amazon.com/clouddrive/sh...hare_link_copy

This last video is when it happened on the freeway and i kept driving car. It had happened before on the freeway and went away after 10 min of driving. This time car cut complete power, no throttle and idled very rough had to coast down to a gas station.

https://www.amazon.com/clouddrive/sh...hare_link_copy

What's weird is when i turned it off and then back on the car was fine and drove normal. Car has been at the dealer for the weekend and they said two codes were given one was cylinder 1 misfire second was an issue with the dme. They cleared the codes and everything was running "good" again. Went to go pick up the car drove maybe 2 miles and back to the same issue, not the very rough idle though. Returned the next day and today get a call saying its coil pack and spark plugs. I am betting the issue is not that and will let them know about your fix.

That last video is what the throttle adaptions are not set. Did you change your SW by chance? That's why the idle is going up/down/up...

Your first video sounds pretty normal to me. Although when you stick the camera near the driver's side charge pipe... it sounds like a vacuum leak there.

You really just HAVE to READ the codes and go from there.

Dackel