[3000GT MR]

Originally Posted by tinnsoldaten

I think I might have a issue there ... I can see little oilwaste in that area.

PVC and cylinder # 6

Check to see if it's clean oil or used. Some times if you spill a little when filling up the car after an oil change it finds its self a home between cyl's 4-6. It may be a little dirty from being under the cover. Just put a little on your finger you'll be able to tell

[tinnsoldaten]

The oil that is there is located on the side of the valve cover , towards the cabin wall.
The row with injectors and sparkplugs is all fine , no leaks there.

Will pull the sparkplug on my cylinder #6 today and see if it is wet or dry. Maybe also swap injectors to be sure its a faulty injector in my case.

[tinnsoldaten]

Found some info that I would like to share:

IMPORTANT: Injectors with index 10 and lower have a different calibration and construction than injectors with index 11 and higher. Due to this difference, the injectors with index 10 and lower and injectors with index 11 and higher cannot be mixed in the same engine.

[litxus]

Crap, I just started to get the stumble (it is rare) and only at idle at stop lights. My spark plugs are new from Burger and replaced cylinder #4 coil. Initially car misfired while driving on the hwy and each time you would accelerate it would just put black smoke out (ECL was on), but after few miles car fixed itself and ECL went off. Code read cyl 4 misfire so I replaced the coil, but thinking that is not the problem.

From looking around here it looks like fuel injectors or intake valves although leaning more toward fuel injectors. Anyone have any ideas and if you have a car past injector recall date how did you get them free?

[AWD Addict]

Had heard someone had good luck with swapping out their VANOS solenoids.

I had the car in for other service, and found that the original ones have been superceded by an upgraded part. I went ahead and had them tossed in.

No dice. Still shaky shaky.

Had some pictures taken of my intake valaves again, and they look terrible. I'm going to talk to the dealer and see if they'll cover another walnut blast. My independent mechanic is asking for a hefty sum.

[va335i]

Glad I found this thread. I had my plugs changed and the dealer told my Cyl 6 plug looks like the injector is running rich. They want to charge me 2k to replace all of the injectors. My 335i runs rough idle when engine is cold then smooths out. So after reading this thread it looks like they are correct and I have an injector failing. But, what I am curious about is if they have a recall on my injectors. My car is 2007 335i.

[Rob S.]

Cant they just see which injector is bad and replace only that one??

[AWD Addict]

Sounds too spendy for injectors. I don't know if it's a recall, but there is a superceding part number.

[See5]

After reading this I'm left wondering what's up with my car as well.

The dealer the HPFP replaced because of long cranks at the beginning of last week. Last weekend I started the car and twice in a row it cranked then died. And it stumbles on startup, like it has to clear its throat as it cranks. The engine physically shakes and it also smells different from the normal sulfur smell.

The dealer says there's nothing wrong but after a cold start, its pretty obvious. It stumbles every once in awhile at idle too.

Don't know what else to do at this point. I'm getting pretty tired of putting this car in the dealer for random stuff. Maybe its just time to move on at this point.

EDIT: Spark plugs were changed about 12K ago. Intake cleaning 10K ago.

[Kruz]

Cant believe I just read this entire thread...[crossing fingers I never have this]

[wielandgeorg]

Hi guys I have a 2007 335i 6AT jb4 and dp's 92k miles I also had that idle stumble

Yesterday I took it to dealer and my buddy put a new hpfp in it because it had the 2aaf plausibility code u can only read it with computer or jb4 won't trigger a CEL

Idle is perfect now with no bumps

Occasionally it goes up to 700rpm but I'm thinkin that's programmed to do so sometimes

However it has not gave me that stumble since

I also have new plugs less then 10k ago

Oh and my Valve cover gasket was bad at 88k so if ua'll experience leak from side of head it's that.

Thanks good luck

[jlva321]

Rough idle just started on the 2007 335i I bought 6 weeks ago, 75K miles stock except for exhaust flap connection unplugged. The car passed a full CPO inspection and is not throwing any codes, I'm checking with an OBD2 scanner and android app. It drove fine for a few weeks before it started.

So far I've added fuel injector cleaner and done a throttle adaption reset. Temperatures just dropped dramatically here so we'll see if that makes a difference.

Long term I'll look at plugs and coils but it will be at least a couple of months before I get to that (assuming it stays just an idle issue). Then on to intake valves, injectors, and throttle body. I've got most of the service records and I think they stuck with the dealer rather than indies, I can see they had the HPFP replaced twice.

Excellent info in this thread, thanks.

[jlva321]

I forgot to mention I also tried cleaning the VANOS solenoids, but I can't remember if I switched them around.

[Redonred1]

Had the same "looking for rpm every 10 seconds" issue.
Was low on gas, put gas, and it went away. Was low in the morning and I noticed the gas smell as well. Filled up last night and no rough idle/gas smell.

Odd cars we have but you gotta love rm! Specially when they go vrrrrooommm

[girliegurl]

Hey All, I'm new to the forum so hopefully I'm posting about this in the right place. In love with my 335i, but it's just out of warranty and I've started having a problem. My car upon cold start idles very rough. The rpm's fluctuate between 500 rpms (almost stalling out) and then shoots up to 3000 rpm's. It's given the check engine light twice while this is happening. I had the code read at autozone and it is P15DF which I saw might be the HPFP. I've been trying to read up on here and have seen that it could be anything from the coil ignition to fuel injectors to vanos solenoids. I will take it to the dealership for the work if it's most likely the HPFP because I read it's covered for 100k miles, but otherwise I want to take it somewhere to get other issues fixed ($$). Has anyone else had this same issue with the same codes?
Oh yeah, and this has been happening for about a month. It drives fine once I actually start driving. As far as gas, I have only been putting in shell V-power for the last few fill ups and same issue.

[AWD Addict]

Originally Posted by jlva321

I forgot to mention I also tried cleaning the VANOS solenoids, but I can't remember if I switched them around.

I replaced mine. Didn't help.

Car still performs well, so I just live with it now. It's still intermittant, which is maddening, because if it's not a constant symptom, you'd think I'd be able to tie it to some external element (weather, fuel, spark plug life, third day of the week in odd numbered months....)

[Jklad]

Same issue here for 10 months now. Doesn't throw any codes. Was getting p29f4 and f5, but seems to be unrelated (I replaced LP fuel sensor and vacuum lines).

Based on forum recommendations, I will try pulling plugs when I do my valve cover next month to check for leaky injector. (I wonder if leaky valve cover near the plugs could affect this?)

Also, someone had a loose rear o2 that cause this same issue, worth a look.

[carlsontheflyer]

I am glad this thread has been resurrected. My car (2010 e92 335i 6MT) also shows unusual idle behavior. the only mods I have are Cobb AP flashed, Cobb FMIC and BMW axle-back performance exhaust. This behavior persists even when I flash my car back to stock.

After a cold start, my car idles first at 1000, then drops to 800, then to 650, which is absolutely normal. It continues to idle at 650ish until it warms up. When oil temps reach around 200 degrees, all of a sudden my idle goes up to 800 and stays at 800 as long as the engine is warm.

And the entire time, at idle, every 20 seconds or so I can feel a momentary slight engine studder, as if it lightly clears its' throat. No codes what so ever, and the car runs perfectly otherwise. Never stalls, and pulls well at partial throttle, and like mad at WOT.

This has been going on for well over a year, and noone can figure out why. It's been at the dealer several times while under warranty and no problems were found.

However, last December, at around 44k miles, the HPFP failed during a hard pull. It went into limp mode and the code was "Cylinder injection shut-off" (I cannot remember the actual code). I turned off the engine, started it back up after a few minutes and it ran well, no limp mode, but the code stayed.

Took it to the dealer and they replaced the HPFP. At the same time they told me one of the injectors was leaking, so they replaced all 6 injectors with the latest ones, and also all 6 plugs and coils.

The car ran perfectly for a little more than 3 months after that. Smooth idle, and always at 650. But recently, about a month ago, it began doing the same damn thing all over again. I can again feel a slight studder every 20 or so seconds, and again, once the oil temps reach about 200 degrees the idle goes up to 800 and stays there.

Also, the intake and valves were walnut blased at 35k miles, and numerous smoke tests were done to try to find any vacuum leaks, but none were found. The car has 49k miles right now.

I am stumped, and it seems everyone else too. Any ideas?

[EastCoast335i]

Originally Posted by carlsontheflyer

After a cold start, my car idles first at 1000, then drops to 800, then to 650, which is absolutely normal. It continues to idle at 650ish until it warms up. When oil temps reach around 200 degrees, all of a sudden my idle goes up to 800 and stays at 800 as long as the engine is warm.

And the entire time, at idle, every 20 seconds or so I can feel a momentary slight engine studder, as if it lightly clears its' throat. No codes what so ever, and the car runs perfectly otherwise. Never stalls, and pulls well at partial throttle, and like mad at WOT.

I have this same exact issue 2008 335i 6MT. It started like most ppl here after the plugs were changed.
Recently had 1 bank of injectors and plugs changed for failed injectors but after that fix I still have the high idle/slight misfire (no code) stumble.
One thing to note, once the car goes into 750-800 idle, the car no longer has slight misfire/vibrations.

For a $50k car with only 56k miles you would hope for more reliability, this car has left me stranded 3 times on the road in the past 3 years

[mimik]

I hope this will help everyone with the same problem but I think I've resolved mine. Originally I had only changed one coil because I had one misfiring cylinder on my OBD reader only in that cylinder. So I replaced all six spark plugs but only one coil. When I spoke to someone who knows Bmw's very well he told me that the minute you start playing around with coils, they are so sensitive that even pulling them out and putting them back in on the new spark plug could actually create a fault enough to cause some of the misfires that we've all been experiencing. So my resolution was simply to replace all six coils. I don't know if this will be a final solution as it seems to fixed the stutter for the past 24 hours but I've never had the car not misfiring for the past two months since I change the spark plugs. Hope this helps.

[AWD Addict]

Originally Posted by carlsontheflyer

I am glad this thread has been resurrected. My car (2010 e92 335i 6MT) also shows unusual idle behavior. the only mods I have are Cobb AP flashed, Cobb FMIC and BMW axle-back performance exhaust. This behavior persists even when I flash my car back to stock.

After a cold start, my car idles first at 1000, then drops to 800, then to 650, which is absolutely normal. It continues to idle at 650ish until it warms up. When oil temps reach around 200 degrees, all of a sudden my idle goes up to 800 and stays at 800 as long as the engine is warm.

And the entire time, at idle, every 20 seconds or so I can feel a momentary slight engine studder, as if it lightly clears its' throat. No codes what so ever, and the car runs perfectly otherwise. Never stalls, and pulls well at partial throttle, and like mad at WOT.

This has been going on for well over a year, and noone can figure out why. It's been at the dealer several times while under warranty and no problems were found.

However, last December, at around 44k miles, the HPFP failed during a hard pull. It went into limp mode and the code was "Cylinder injection shut-off" (I cannot remember the actual code). I turned off the engine, started it back up after a few minutes and it ran well, no limp mode, but the code stayed.

Took it to the dealer and they replaced the HPFP. At the same time they told me one of the injectors was leaking, so they replaced all 6 injectors with the latest ones, and also all 6 plugs and coils.

The car ran perfectly for a little more than 3 months after that. Smooth idle, and always at 650. But recently, about a month ago, it began doing the same damn thing all over again. I can again feel a slight studder every 20 or so seconds, and again, once the oil temps reach about 200 degrees the idle goes up to 800 and stays there.

Also, the intake and valves were walnut blased at 35k miles, and numerous smoke tests were done to try to find any vacuum leaks, but none were found. The car has 49k miles right now.

I am stumped, and it seems everyone else too. Any ideas?

It's spooky how similar your experience has been to mine.

How good are you with running good gas? I've been experimenting with different brands.

[carlsontheflyer]

Originally Posted by AWD Addict

It's spooky how similar your experience has been to mine.

How good are you with running good gas? I've been experimenting with different brands.

I always use QuickTrip premium gas. It's a top tier fuel and recommended by BMW. I have been using it on all my cars for over 10 years.

My car is still running as I described. I have been logging data in different situations, and I am pretty sure I have narrowed it down (with the help of a couple of knowledgeable members on this forum) to the high pressure fuel pump, or specifically to the IPR (Injection Pressure Regulating) Valve. It sticks and doesn't function properly. Unfortunately it's integrated into the HPFP. I have logged the HPFP values (requested and actual) and they are all over the place, never matching and wildly fluctuating.

The HPFP will have to be replaced (again), but since there are no codes, I'll have a hell of a time convincing the BMW dealership to replace it under the HPFP warranty. My regular factory warranty ended 6 months ago.