[bigjilm]

I just had my '11 335i in for an oil change in October, and they updated my software while I was in (part of a battery warranty thing, I believe). They told me it was a benign change, related to improved idle.

Since then, I've noticed a few things, and I'm wondering if anyone else has noticed:
-my engine seems to 'hunt' at idle. It's too subtle to see on the tach, but the engine seems to surge about once per second. This happens once or twice a week for an entire trip.
-I've stalled my motor four times. Twice, while I was waiting in the middle of intersections waiting to turn left. Today, it happened while the car was warming up - about 10 seconds after I started it, and before I even had a chance to get it in gear.
-The motor seems to run smoother and with less drama, but also feels like it could be down on power. This could be in my head, though.

I have a coworker with the same car and his software was updated a month earlier, and he says that he also feels like his car has less power now. He hasn't had any stalling and hasn't notice the idle hunting though.

Anyone else seen any of these symptoms? I'd take it into the dealer if this was a serious enough set of problems to take a day off work, and I kinda doubt they'll be able to do anything if this is caused by software. Thoughts?

-Jimbo in Toronto

[chromisdesigns]

Take it to the dealer now -- it should not be stalling, whatever the reason.

[neteagle]

Originally Posted by bigjilm

I just had my '11 335i in for an oil change in October, and they updated my software while I was in (part of a battery warranty thing, I believe). They told me it was a benign change, related to improved idle.

Since then, I've noticed a few things, and I'm wondering if anyone else has noticed:
-my engine seems to 'hunt' at idle. It's too subtle to see on the tach, but the engine seems to surge about once per second. This happens once or twice a week for an entire trip.
-I've stalled my motor four times. Twice, while I was waiting in the middle of intersections waiting to turn left. Today, it happened while the car was warming up - about 10 seconds after I started it, and before I even had a chance to get it in gear.
-The motor seems to run smoother and with less drama, but also feels like it could be down on power. This could be in my head, though.

I have a coworker with the same car and his software was updated a month earlier, and he says that he also feels like his car has less power now. He hasn't had any stalling and hasn't notice the idle hunting though.

Anyone else seen any of these symptoms? I'd take it into the dealer if this was a serious enough set of problems to take a day off work, and I kinda doubt they'll be able to do anything if this is caused by software. Thoughts?

-Jimbo in Toronto

I have the same exact problem. Mine did it even before the software update (which I paid for out of my own pocket). It has done it since mile 1. Doesn't throw any codes when it stalls so dealer is telling me nothing can be done. Close to selling the car. Did they figure out what your issue was? And, the car is down on power...there is no doubt. It actually pulls hard sometimes and then sometimes it does not pull. Very inconsistent...

[GMWNashville]

if the car stalls...and there isnt any faults..the best route to go is to allow the shop foreman to drive the car until it does it for them...once duplicated and still no faults a case should be opened with BMW to resolve the issue.

[Biganesh]

I recently had a problem with my 335i coupe (N55). Went in for battery recall, and came out with a car that stalls when idle or at slow speeds. Anyone else with this issue?
Roger

[neteagle]

I've had it in the shop for the last going on two years. They are absolutely clueless...replaced HPFP and even a new Throttle
Body. No fix. Very frustrated. Car is a POS. 2nd lemon in a row. If you figure out what it is, please post back...

[bigjilm]

I got a partial answer. The last time in, the advisor told me that the last software update did something to reduce the demands on the turbos, and that there was a unnoticeable reduction in power. The idle is also somehow affected, so they raised the idle RPM setting to compensate.

My car still bogs, but hasn't stalled. I suspect the idle adjustment has sufficiently masked the idle problem. I also haven't had a good stretch of dry pavement to test the power, but I think it might be down for good. I'd love to see a dyno run to see if we have something actionable here.

[neteagle]

They did the same thing on my car. Still almost stalls all the time. Got a GoPro last week. I'm going to get evidence to take back to the dealer.

Same issue on power. It definitely is inconsistent at best.

I don't really think it is the software as I have an early production 2011 and paid to have the software updated.

[e90Luis]

I'm having the same problem. I took the car to the dealer to have the intake blasted with walnut shells and when I got the car back it ran great. One week later after a fill up the car began to feel as if it is lacking power. Almost as if the turbos weren't kicking on til a certain RPM. It's odd and the dealer told me there's nothing wrong with the car

[pylt]

Originally Posted by neteagle

They did the same thing on my car. Still almost stalls all the time. Got a GoPro last week. I'm going to get evidence to take back to the dealer.

Same issue on power. It definitely is inconsistent at best.

I don't really think it is the software as I have an early production 2011 and paid to have the software updated.

Yes, I'm having the same problem, except the power is mostly there--it's the stalling that's driving me nuts.

If anyone has any advice I'd appreciate it. Stalls once or twice a day, then works fine for a week or more.

Two dealers have had my '11 335i now and seem to be unable to duplicate the problem, and there are NO codes. I was able to show/demo the erratic idle (650 to 900ish, then back to normal, followed by another cycle in 10 to 40 seconds). These seem to occur only when it's hot (>100F here in Texas), but so far the second dealer has had the car for two days and counting. Again, NO codes.

Very frustrating, and remarkably dangerous as the car dies when driving so no power steering assist.

**How did you mount the camera--that appears to be the only way to prove the problem exists?**

In the meanwhile, will file a complaint with NHTSA soon. Can't let my wife drive the car due to concerns re: loss of power steering. Plus, perhaps BMW will recall when the government makes them (about 4 or 5 years from now given BMW's history), but would much prefer a solution ASAP.

[bigjilm]

The original problem with my car seems to be gone. I have a nice, steady idle, and I haven't had it stall since they updated the software.

However, my butt dyno tells me that I'm down on power for sure. If I had more confidence in either my dealer or BMW in general, I'd be getting my software updated again to see if my power comes back, but who the hell knows what other problems lurk in the newest flash.

[neteagle]

GoPro Motorsports edition with suction mount. Stick to sunroof and let hang down at an angle so you can see the tach.

They have acknowledged the problem, but still have not found a solution... They have even gotten engineers in Germany involved...they are clueless about what could be the source of the issue....time to sell this bag of junk...

Originally Posted by pylt

Yes, I'm having the same problem, except the power is mostly there--it's the stalling that's driving me nuts.

If anyone has any advice I'd appreciate it. Stalls once or twice a day, then works fine for a week or more.

Two dealers have had my '11 335i now and seem to be unable to duplicate the problem, and there are NO codes. I was able to show/demo the erratic idle (650 to 900ish, then back to normal, followed by another cycle in 10 to 40 seconds). These seem to occur only when it's hot (>100F here in Texas), but so far the second dealer has had the car for two days and counting. Again, NO codes.

Very frustrating, and remarkably dangerous as the car dies when driving so no power steering assist.

**How did you mount the camera--that appears to be the only way to prove the problem exists?**

In the meanwhile, will file a complaint with NHTSA soon. Can't let my wife drive the car due to concerns re: loss of power steering. Plus, perhaps BMW will recall when the government makes them (about 4 or 5 years from now given BMW's history), but would much prefer a solution ASAP.

[pylt]

Originally Posted by neteagle

GoPro Motorsports edition with suction mount. Stick to sunroof and let hang down at an angle so you can see the tach.

They have acknowledged the problem, but still have not found a solution... They have even gotten engineers in Germany involved...they are clueless about what could be the source of the issue....time to sell this bag of junk...

Brilliant--had never thought of a suction mount via the moonroof as we tend to keep our moonroof shades closed here in Texas (too frigin' hot!).

Will contemplate as my next step if get blamed (again) as "driver error." That's the "solution" posed by my first dealer's service shop--wanted to scream that I've been driving a manual for about 3 and a half decades and I know what the hell I'm doing! (Not to mention how much customer goodwill it generates when they BLAME THE CUSTOMER for a problem.) My second dealer has had my 335i now for about a week with no other communication besides, "Can't duplicate the problem, may I allow our shop foreman to take the car home?" last week.

Is he still taking it on joy rides? What's the status of my repair?!?

Do most dealers do this? I expect more from BMW--like a status update every other day or so. Instead, from both dealers it's been 100% silence unless I call them. Seems rude to me, especially at this price point. Comments?

[bigjilm]

Do all dealers do this? In my part of the world, yes.

I'm the nicest, most patient person possible, going way out of my way to be friendly and accommodating, and every BMW dealer eventually does something insane to me.

I love the cars - hate everything else about BMW at this point.

[pylt]

Originally Posted by bigjilm

Do all dealers do this? In my part of the world, yes.

I'm the nicest, most patient person possible, going way out of my way to be friendly and accommodating, and every BMW dealer eventually does something insane to me.

I love the cars - hate everything else about BMW at this point.

THIS is so true.

Just got my car back from the second dealer. Despite 100 miles of driving around over the weekend, they found nothing wrong.

Looks like I know why: it appears they filled the tank full before their extended test drive, despite advising them that it never seems to occur with more than 3/4 tank.

Smart. Really smart.

Where do they find such men?

Time to buy a GoPro or that data logger software and start driving around with my laptop. What a waste of my time; I am SO tired of being an unpaid member of BMW's Beta Test Team!

[bigjilm]

Originally Posted by pylt

THIS is so true.

Just got my car back from the second dealer. Despite 100 miles of driving around over the weekend, they found nothing wrong.

Looks like I know why: it appears they filled the tank full before their extended test drive, despite advising them that it never seems to occur with more than 3/4 tank.

Smart. Really smart.

Where do they find such men?

Time to buy a GoPro or that data logger software and start driving around with my laptop. What a waste of my time; I am SO tired of being an unpaid member of BMW's Beta Test Team!

Conspiracy theory time - maybe they know all about your problem, have no way to fix it, and would rather just send you on your way. I have two friends with n55's and both have been in to their dealers for the same problem.

Software updates come straight from hq, so I'm sure that leaves them in a tough position. They can't tell you it can't be fixed, can't blame it on hq, and can't fix the problem. "unable to reproduce" might be all that's left for them.

My car, for now, does seem to be stable, but it's come with a price - they done something to reduce the power and that really freaking bugs me.

[Meeni]

If it does it less when the tank is full, it could be a bad mix of ethanol. Change gas station just to see if it helps.

[pylt]

Originally Posted by Meeni

If it does it less when the tank is full, it could be a bad mix of ethanol. Change gas station just to see if it helps.

Gas isn't much of a factor as we use Top Tier gas, as recommended.

It's getting warmer here in Texas and so it's stalled again early this week.

Anyone have a solution yet?

[Meeni]

Originally Posted by pylt

Gas isn't much of a factor as we use Top Tier gas, as recommended.

Top tier gas has a better additive package. This is good and all.

But most gas station in the US have their tank contaminated with water. Ethanol gas is especially prone to capturing water and separating in layers if kept still too long. Even good brand gas stations can have this issue, it has more to do with the location itself than the brand.

The fact that the problem is present only when the tank is almost empty points to water contamination and/or bad ethanol gas to me (that is, gas in with petrol and ethanol have separated and are no forming 2 layers, one being normal fuel, the other one more or less pure alcohol).

May not be that, but it is the simplest thing to try and cost nothing. Good luck finding!

[neteagle]

This is a wide-spread N55 issue. Has nothing to do with gas. BMW is working on a DME software fix that was supposed to be released at the end of March. They are running behind. This problem is related to their idle control logic.

Water is heavier than gasoline. You would see water issues immediately after filling up not when the tank is low...

[Meeni]

Originally Posted by neteagle

This is a wide-spread N55 issue. Has nothing to do with gas. BMW is working on a DME software fix that was supposed to be released at the end of March. They are running behind. This problem is related to their idle control logic.

Didn't knew about this for the N55. Makes sense indeed.

Water is heavier than gasoline. You would see water issues immediately after filling up not when the tank is low...

The contamination problem is not the same with Ethanol gas. Unlike pure gasoline which doesn't mix with water, e85 does. When the tank is full, the fuel is fresh and water is evenly diluted. Only after some time does the water (and the Ethanol itself) "condensate" and form pockets.

[bigjilm]

This problem is definitely related to the change of seasons, and that makes me believe it might be 'winter gas' additives (perhaps ethanol or similar). I haven't stalled yet, but the instability in my idle is back and the weather has just changed to spring this week here in Toronto.