[BMR335]

I have had this exact same issue, both with and without my COBB AP installed, for the past 8k miles. I am a 2/07 build, auto transmission, with 35k miles. I use bottles of Techron from time to time and it does seem to decrease the frequency for awhile, but invariably the stumbling comes back.
I was picking Jason@Cobb's brain about this, and he suggested getting the injectors cleaned at the dealership with their specially designed crushed-walnut-shell blaster...
I see that a few on here have tried this, but without full resolution for those who have posted. Has it resolved the issue for anyone?

[gdawg20001]

Glad I've come across this thread but amazed at how many people have this issue with no resolution.

I too replaced plugs about 2k miles ago and have also been experiencing these hiccups and stumbles ever since.

Car has been running a procede for approx. the last 30k miles and the newest V5 for the last 5k. No issues at all until changing plugs.

Subscribed and interested to see if anyone finds a solution.

Although, it doesn't seem to fix the issue, I know I'm due for a cleaning... What's the walnut shell blasting seem to run most people?

[AWD Addict]

Both of my walnut shell blastings were great for performance, but didn't help the blip, and were done underwarranty. Shouldn't cost more than a few hundred bucks, but I'm not sure.

I'm on 6 new inectors and plugs right now and my last valve cleaning was pretty recent,and I have still have it.

[DriM3]

jesus christ this is awful!!....mine too just started acting funny today. its the second warm week we've had this season and while out on a drive it just randomly started vibrating.

Im in shock that there seems to be no answer on how to fix this

[robc1976]

Mine to now, Had MY HPFP replaced yesterday, (Still have long starts??) but I have replaced plugs, coils and my build date is a 11/01/06 335i. Before my fuel pump was replaced I had misfires on cyl 2 & 5. I am still getting that hesitation/hiccup/jolt at idle. sucks is the only word to discribe it. How much would injectors cost out of pocket? probally $400.00-$500.00 a piece I am guessing.

[enrita]

Originally Posted by robc1976

Mine to now, Had MY HPFP replaced yesterday, (Still have long starts??) but I have replaced plugs, coils and my build date is a 11/01/06 335i. Before my fuel pump was replaced I had misfires on cyl 2 & 5. I am still getting that hesitation/hiccup/jolt at idle. sucks is the only word to discribe it. How much would injectors cost out of pocket? probally $400.00-$500.00 a piece I am guessing.

http://www.ebay.com/sch/i.html?_from...585261+&_fvi=1

[AWD Addict]

dead linky ^

[robc1976]

Originally Posted by enrita

http://www.ebay.com/sch/i.html?_from...585261+&_fvi=1

Thanks!!

[robc1976]

Originally Posted by AWD Addict

dead linky ^

Didn't work on phone but worked on PC.

[robc1976]

Here also: (Brand new)...not a bad price! this for a 2007 though.

http://www.trademotion.com/parts/200...onent=INJECTOR

[AWD Addict]

Jesus. $600 for a full set of injectors.

*gag

[robc1976]

Originally Posted by AWD Addict

Jesus. $600 for a full set of injectors.

*gag

BMW Quoted me $497.00 per injector!!!!

Total of $2,982 (installed maybe??) F-that!! for that price I will deal with the studder LOL!!

[Syndicategt]

Originally Posted by robc1976

BMW Quoted me $497.00 per injector!!!!

Total of $2,982 (installed maybe??) F-that!! for that price I will deal with the studder LOL!!

Are you sure that didn't include plugs,coils, and install? Either way, it's a rip off as install and coding are super easy.

[AWD Addict]

Originally Posted by robc1976

BMW Quoted me $497.00 per injector!!!!

Total of $2,982 (installed maybe??) F-that!! for that price I will deal with the studder LOL!!

Thieves!

Won't fix the studder anyhow. I'm on all new injectors and plugs. We've ruled those out as the culprit. There's a definite relation to the ECU adaptations I think. WHenever my car is re-flashed, it's good for a couple days, then it slowly comes back.

[marv85]

Originally Posted by robc1976

BMW Quoted me $497.00 per injector!!!!

Total of $2,982 (installed maybe??) F-that!! for that price I will deal with the studder LOL!!

buy the injectors from ECStuning or Tischer, follow Vasillalov's DIY and you're good to go for ~800$

[prelude2perfect]

Same issue here. No codes so BMW said they can't fix anything under warranty without a code. Spark plugs were replaced by myself a while ago but, I don't remember if that is when it started running rough or not. I was definitely thinking injectors or hpfp but, I'm clueless now. Maybe I should reset the adaptions? I dunno

Wish someone would figure this out. If I was throwing a misfire code at least I could focus on the problem but, with no codes I have to check everything. I'll be checking coils next but, they have been replaced in the past under warranty. Injectors and HPFP have been replaced long before the problem started. Maybe it was the new plugs that caused it. I'm at 68k miles FYI

[PR3CI5N]

Sounds more like the LPFP since this is occurring at idle. Doubt it's the HPFP but you're spark plugs could be due for a replacing as well.

[Mangler]

Interesting. I am taking my car back in today for a full original order to be installed on my ecu so they can then reflash all the possible new updates to try to get rid of this stumbling issue. They have already replaced all the coils/plugs/injectors at the same time with no change. They did find some iffy vacuum hoses that were replaced also. No change. It feels like a lean misfire but no codes.

T

[AWD Addict]

Originally Posted by PR3CI5N

Sounds more like the LPFP since this is occurring at idle. Doubt it's the HPFP but you're spark plugs could be due for a replacing as well.

It's not the HPFP, and it's not plugs. Almost everyone in this thread with the problems has newplugs. In fact, it appears the condition tends to arise immediately after new plugs have been added.

The LPFP is interesting.

[Tzu]

My idle stumbles have gotten considerably worse after new plugs. Previously, it would only raise RPMs after every 5th or so drive. Now it does it on every startup or after a short drive. Injectors are coded correctly.

I'm going to try cleaning the coil where it contacts the plug head, and I'm beginning to think 17ft.lbs is too much to torque these. Just a theory though. Correct me if I'm wrong, but wasnt there an idle adaptation value in INPA somewhere? I havnt found it yet because my version is still in German.

[robc1976]

Originally Posted by Tzu

My idle stumbles have gotten considerably worse after new plugs. Previously, it would only raise RPMs after every 5th or so drive. Now it does it on every startup or after a short drive. Injectors are coded correctly.

I'm going to try cleaning the coil where it contacts the plug head, and I'm beginning to think 17ft.lbs is too much to torque these. Just a theory though. Correct me if I'm wrong, but wasnt there an idle adaptation value in INPA somewhere? I havnt found it yet because my version is still in German.

Makes sense, I did the throttle reset and unplugged my battery for 1 hr and the stumble is gone? This could just be the 1X it didn't do it though. I am still getting long starts after my HPFP was installed so it is going back today.

[Tzu]

I've done an adaptation reset as of two weeks ago chasing down something else. No change in idle sputters. I'll try again soon.