[AWD Addict]

At idle on a warm engine, no fan or A/C, I'm getting a rough idle. A kind of irregular stutter that i can feel in my seat and on the shifter. Even my brother in the passenger seat feels it.

I've had it for a long time, and just thought it was part of hte HPFP issue, but I've had 3 replaced, and I'm currently on the "fixed" one, and i still have it.

At roughly 20k miles, the car went through a 1wk diagnostic with a ton of tests and eventually they took off the valve cover, and the whole valve train was "gummed up" I was supposed to get pictures but never did. They cleaned them out, and the car ran smoother and faster than it had since it was new, and the rough idle went away...


...for a while.

Since then, now approaching 40k miles (and the end of my warranty - when I want this fixed by!) - the stutter is back and as bad as ever. It came on slowly, and gradually. I figured my HPFP was on the outs again, so i took it in again and they said to replace it with the newest version. I've been questioning these last few visits how this problem could be the fuel pump if it's not doing anything after so many tries, but my SA said this was it. No dice. Car still randomly shakes or jerks, or kind of stumbles at a redlight. Needle just keeps hunting for rpms. 800, 650, 400 (jerk) 700.

The car starts with a kind of stumble into idle too (clumsy start), and it stalled about a month ago on me (fully warmed up.)

MY rpms move up and down, irregularly and intermittently sometimes stable with the jerks, sometimes up and down 200-300 rpms.

I'm thinking they should take the valve covers off again, but my SA tells me if they do it, and find nothing, I'm on the hook for a 7hr job.

Thoughts?

[AWD Addict]

I had forgot about this thread. More below.

http://www.e90post.com/forums/showth...ight=rpms+idle

The video on this thread sounds the same, just with the non-stock exhaust obviously.

http://www.e90post.com/forums/showth...ight=rpms+idle

This one sounds the same too, particularly post 19 where flukey says he can instigate the stutter with a throttle blip. Also post 39 mentions it's worse when it rains. I think mine is too.

http://www.e90post.com/forums/showth...ight=rpms+idle

[ren]

I have the exact same thing, but mine started after replacing the spark plugs. Happens only when the engine is warm, and more often when A/C is off as you described.

I couldn't get the tech replicate this when I took the car in the last two times, so I gave up.

[Beemw335]

Hmmm well it could be
Hpfp. (but you have the latest one so prob not the pump)
Spark plugs
Injectors

[AWD Addict]

Reading these other threads, I'm starting to feel that this is a valving related issue.

[redwinger]

I have the same thing. 39k miles. new HPFP and injectors. I figured it was normal

[Jimefam]

Get their little fix and when it does it after that record it and take the video to the dealer and ask them if that's normal. If it's not then they NEED to find the cause and your not on the hook for ish if they don't find it then as they have to do whatever to fix the issue.

[ScaredOnce]

Consequence of DI? Fuel additives not getting to where they were meant to work? idk. I've thought about that scenario though...

[KC335]

after my HPFP and 6 new injectors i am having the same thing happening to me. When its going, its smooth, but when it sits..it starts to shake a bit..and once the temp is warm, it starts to hunt for rpms 600, 750, 600, 700, etc like what AWD Addict said. Called the SA and he said that it might be the the addictives in the gas. I always use Chevron 94 and he said that they've been telling people to start using Shell 91 Vpower. I'm bringing my car in tomorrow for warranty (unrelated issue), and he will take a look. My warranty is also running out so i want to get this problem solved.

[AWD Addict]

It's not the damned gas. I'm so tired of hearing all these Service Departments saying it's bad gas. We have the highest quality gas in the world in the US, and most of us are buying high grade brand name gas anyways.

You'd think the entire supply of gas were shit by the way these guys throw that around.

Was it the bad gas that gummed up my valve train too? Give me a break. I think these cars are running pig rich, and the valving is suffering.

I'd bet dollars to donuts if they took of my valve covers again, they'd find the same gummed up mess.

dR

[Perfectus]

Originally Posted by erensf

I have the exact same thing, but mine started after replacing the spark plugs. Happens only when the engine is warm, and more often when A/C is off as you described.

I couldn't get the tech replicate this when I took the car in the last two times, so I gave up.

Same thing happened to me after BMW replaced my spark plugs. I fought with them for a month before I gave up. I'm going to be replacing my sparks again soon after 25k miles on the current ones.

Did your COBB flash make it better or worse?

[KC335]

Originally Posted by AWD Addict

It's not the damned gas. I'm so tired of hearing all these Service Departments saying it's bad gas. We have the highest quality gas in the world in the US, and most of us are buying high grade brand name gas anyways.

You'd think the entire supply of gas were shit by the way these guys throw that around.

Was it the bad gas that gummed up my valve train too? Give me a break. I think these cars are running pig rich, and the valving is suffering.

I'd bet dollars to donuts if they took of my valve covers again, they'd find the same gummed up mess.

dR

I agree with you, we do have the highest quality gas here in North America. The SA are blaming their problems on gas rather then themselves. When i got my car towed into the dealership they said that i had the fuel level too low (I had a quarter of a tank left). I told them this never happen before and i had it lower than this before and its smooth. Then next day they told me it was the HPFP.

[ren]

Originally Posted by Perfectus

Same thing happened to me after BMW replaced my spark plugs. I fought with them for a month before I gave up. I'm going to be replacing my sparks again soon after 25k miles on the current ones.

Did your COBB flash make it better or worse?

I replaced my spark plugs myself, so I couldn't tell them that at the dealership, they would just blame it on something stupid.

I'm almost certain that it is one of my coils, but I don't know which one. When I was replacing the spark plugs, I realized that the metal connector inside the coil was almost bound to the spark plug. I think that contact point on the coil is deformed and causes a connection problem with the new spark plug. I don't know why it would happen when the car is warm and at idle. But again, I am no expert on this, so it's just my speculation.

I don't think any tune would make a difference. It was the same when I had my Procede, and I still have it with no tune installed. I haven't tested it with Cobb because I haven't been able to flash my car yet due to some communication issues between AccessPort and my ECU. I'm waiting for Cobb to find a solution, Rob is working hard on it.

[AWD Addict]

If it were a rich condition problem, the tune might have an effect, but only if the resulting negative condition were remedied first. The tune may not "fix" the problem, but absent a problem in the first place, it may not create one similarly to the stock condition.

I'm glad I'm not alone though. The links I provided above,and in this thread alone, there must be 30 of us.

[M3 Eater]

I have jb4, just reset all the adaptions except throttle as its a bitch sometimes to do right. I reset the ECU and reflashed jb4's firmware. Car runs very strong but when warm I can feel small misses in the seat and the steering wheel. Its downright rough idle. I have an intake as well and was wondering if that might affect the idle. The tune and the ECU should adapt and the car should be running smooth. Just changed all the plugs and resat the coils, replacing one bad coil. Maybe another coil or two are on their way out?

I had oil leaking from the oil cap and it got on one of the coils and ruined it( I think). Becuase I have a catchcan, I paid for the parts as it was messing up the crankcase pressure and making the oil spill over so.... not sure what to do next.. Car is running so good until its time to sit at a light or something.

[AWD Addict]

I'm unmodded FYI.

[Rob.K]

I had the same problem for a while. Noticeable jerks and shakes and RPM drops by 50-250 RPM.
First time I complained about it I was told it was normal for these cars. Second time around they found the throttle body to be loose?
They fixed that and I've been sitting at a steady 600 RPM ever since.

[ren]

Originally Posted by Rob.K

I had the same problem for a while. Noticeable jerks and shakes and RPM drops by 50-250 RPM.
First time I complained about it I was told it was normal for these cars. Second time around they found the throttle body to be loose?
They fixed that and I've been sitting at a steady 600 RPM ever since.

It's worth giving it a try. Thanks for the info.
The AFE throttle spacer kit says it should be tightened to 10Nm here: http://afepower.com/catalog/46-31002/is.pdf

[Rob@Cobb]

Originally Posted by AWD Addict

At idle on a warm engine, no fan or A/C, I'm getting a rough idle. A kind of irregular stutter that i can feel in my seat and on the shifter. Even my brother in the passenger seat feels it.

I've had it for a long time, and just thought it was part of hte HPFP issue, but I've had 3 replaced, and I'm currently on the "fixed" one, and i still have it.

At roughly 20k miles, the car went through a 1wk diagnostic with a ton of tests and eventually they took off the valve cover, and the whole valve train was "gummed up" I was supposed to get pictures but never did. They cleaned them out, and the car ran smoother and faster than it had since it was new, and the rough idle went away...


...for a while.

Since then, now approaching 40k miles (and the end of my warranty - when I want this fixed by!) - the stutter is back and as bad as ever. It came on slowly, and gradually. I figured my HPFP was on the outs again, so i took it in again and they said to replace it with the newest version. I've been questioning these last few visits how this problem could be the fuel pump if it's not doing anything after so many tries, but my SA said this was it. No dice. Car still randomly shakes or jerks, or kind of stumbles at a redlight. Needle just keeps hunting for rpms. 800, 650, 400 (jerk) 700.

The car starts with a kind of stumble into idle too (clumsy start), and it stalled about a month ago on me (fully warmed up.)

MY rpms move up and down, irregularly and intermittently sometimes stable with the jerks, sometimes up and down 200-300 rpms.

I'm thinking they should take the valve covers off again, but my SA tells me if they do it, and find nothing, I'm on the hook for a 7hr job.

Thoughts?

A thought maybe carbon buildup in the intake ports. Pulling the intake manifold to look is not too difficult for the mechanically inclined.

Cheers,
Rob

[AWD Addict]

Thanks Robb!

I do suspect it's valve buildup related, though the throttle body fix above is certainly worth looking at as well.

[smk1028]

I had exactly the same problem in my '08 (no mods)-- fuel pump and injectors replaced, then the slightly rough idle. I took it to the dealership and the Service Mgr sat with me in it for about 5 minutes and said that he felt it. I have 42k miles so he offered to clean carbon buildup. They took the car for 4 days, said they found "some, but not much" buildup, returned to me. It was okay for about 2 weeks but I'm starting to notice it again. Almost out of warranty, and starting to worry. Also, now that it's warm up and I'm driving with the windows down I'm noticing a more distinct rumble when downshifting to slow down-- like you'd hear on an old car-- wondering if this is related? Oh, and to top it off I hear what I think is the waste gate rattle coming on!

LOVE LOVE LOVE this car, but honestly, will this ever end?! I keep telling myself that at some point I will get through all of the "typical" 335i problems and then the car will be good, but I'm starting to lose hope....

[AWD Addict]

For the record, I went stumble free after a service soon after my last post in this thread.

Then about 60 days ago, I had some work done (new flash, new plugs, oil change, etc.) and they brought the car down the ramp for me, and it was misfiring something fierce.

They sent me home in a loaner, and hte next day they said they hadn't reset something after then new plugs were installed ( ). Well, sure enough, the car has the stumbling idle again.

That, combined with people talking about ignition (plugs and coilpacks), I'm wondering if this isn't a fuelling or valving issue at all, but an ignition one? Is this a bad connection/misfire type of issue?

Anyone else had any success getting rid of the stumble?