[markus037]

Im taking my car in on the 13th to get the vanos bolts recall done and was wondering if there may be any TSBs or software updates for the rough idle. My car will idle real low and then jump back to normal. it happens at red lights mostly. today was pretty bad but no CEL on.the idle will be smooth at about 600 rpms then drop to below 500 then jump back up. feels like its going to die sometimes. really annoying but seems to be common on these things. When i spoke to the rep on the phone she said it may be related to the vanos recall.

[JTDahl]

+1 thought it was the MAF but sadly enough the rep did not have a solid answer. I too have a N51. Whats your mileage like?

[paulm3251]

Originally Posted by markus037

Im taking my car in on the 13th to get the vanos bolts recall done and was wondering if there may be any TSBs or software updates for the rough idle. My car will idle real low and then jump back to normal. it happens at red lights mostly. today was pretty bad but no CEL on.the idle will be smooth at about 600 rpms then drop to below 500 then jump back up. feels like its going to die sometimes. really annoying but seems to be common on these things. When i spoke to the rep on the phone she said it may be related to the vanos recall.

Might be eccentric shaft sensor....just had mine done similar symptoms and it fixed the problem. At red lights I would have idle surging felt like it was going to stall. Checked the eccentric shaft sensor and now it runs fine no problems with idle or surging.

[paulm3251]

Cylinder 4 misfire as well forgot to add that.

[Tim603]

I used to have the same issue. I checked my Eccentric Shaft Sensor and it was fine. I changed my plugs with new NGK ones, double checked proper gap and it fixed the rough idle.

My Car
328xi N51
148k miles

Possible Fixes
-New plugs with proper gap (http://www.e90post.com/forums/showth...&highlight=gap)
-Clean MAF
-Check Eccentric Shaft Sensor
-Clean/ Change Air filter

[markus037]

i have had issues with cyl 4 5 and 6 misfires a few weeks back but the codes never returned. i was thinking eccentric shaft sensor too, what is the way to check it? plugs were replaced 6k ago with OEM plugs. no oil leaks either. ill have to try cleaning the maf and seeing what happens. air filter was replaced not too long ago either.

[markus037]

as far as mileage go i average 22mpg but most of my driving is side roads. on the highway its probably closer to 30

[driverman]

Have you tried a bottle of fuel injector cleaner?

Chevron Techron Fuel System cleaner.

I had the same symptoms and one bottle of the cleaner cleared it up. Worth a try.

[jc5988]

Originally Posted by markus037

Im taking my car in on the 13th to get the vanos bolts recall done and was wondering if there may be any TSBs or software updates for the rough idle. My car will idle real low and then jump back to normal. it happens at red lights mostly. today was pretty bad but no CEL on.the idle will be smooth at about 600 rpms then drop to below 500 then jump back up. feels like its going to die sometimes. really annoying but seems to be common on these things. When i spoke to the rep on the phone she said it may be related to the vanos recall.

that happens to me only for first 10k miles and during cold start only..

how many miles you got on yours?

[bNks334]

2013 128i N51 with 13k miles here...

I am getting the same issue. My car seems like it wants to stall on cold starts and even sometimes after warmed up. With the weather changing it has become much more prominent. Honestly, it is downright dangerous at times. The car will surge forward when rolling to a stop (as the engine stumbles). It also surges forward when pulling into and backing into parking spots. I doubt insurance will believe I hit someone because my engine was stumbling.

I cant imagine this is a fuel system issue. I always fill with HESS brand premium gas (93). With my mileage and age I cant imagine there is any buildup. Fuel injector cleaner is not going to help. I know this is what the dealer is going to suggest too. Any advice on how to approach this when I bring the car in for service in December? I want this fixed!

Any help would be appreciated!

[markus037]

i just dumped a bottle of the liqui moly jectron in and i always use sunoco 93 in my car. currently has 66k on it. im wondering if its a software issue at this point.

[Mavus]

The rpm can be coded and you can increase it by ~200. Another fix is a tune. Evolve does an amazing job with their tune. My idle rpm has almost no fluctuations. If all parts are healthy it's a s/w issue.

[markus037]

maf is reading OK too. goes up with idle and holds steady. im going to talk to the dealer if theres anything they can do. if not then perhaps ill look into aftermarket tuning. im sure it can get rid of the annoying flat spot in the mid rpm range too.

[parabola]

Originally Posted by bNks334

2013 128i N51 with 13k miles here...

I am getting the same issue. My car seems like it wants to stall on cold starts and even sometimes after warmed up. With the weather changing it has become much more prominent. Honestly, it is downright dangerous at times. The car will surge forward when rolling to a stop (as the engine stumbles). It also surges forward when pulling into and backing into parking spots. I doubt insurance will believe I hit someone because my engine was stumbling.

I cant imagine this is a fuel system issue. I always fill with HESS brand premium gas (93). With my mileage and age I cant imagine there is any buildup. Fuel injector cleaner is not going to help. I know this is what the dealer is going to suggest too. Any advice on how to approach this when I bring the car in for service in December? I want this fixed!

Any help would be appreciated!

Your car must be under warranty, so I'd just take it to the dealership. I've had a similar issue on my 2011 328 with N51 engine, on every cold start it would run rough, rpms dropping and surging, 10 min of driving and it would go away.
Eventually I took it to the dealer, and they said they had to reprogram DME, there was a service bulletin for it, so it was a known issue. Car had about 28k miles at the time. Problem never returned after that.

[bNks334]

Originally Posted by parabola

Your car must be under warranty, so I'd just take it to the dealership. I've had a similar issue on my 2011 328 with N51 engine, on every cold start it would run rough, rpms dropping and surging, 10 min of driving and it would go away.
Eventually I took it to the dealer, and they said they had to reprogram DME, there was a service bulletin for it, so it was a known issue. Car had about 28k miles at the time. Problem never returned after that.

Thanks for the info. I will try to find the service bulletin for reference when I bring it in. However, I would've thought that if this was a software issue it would've been corrected by the 2013 model year.

[hongsc]

Originally Posted by parabola

Your car must be under warranty, so I'd just take it to the dealership. I've had a similar issue on my 2011 328 with N51 engine, on every cold start it would run rough, rpms dropping and surging, 10 min of driving and it would go away.
Eventually I took it to the dealer, and they said they had to reprogram DME, there was a service bulletin for it, so it was a known issue. Car had about 28k miles at the time. Problem never returned after that.

For the past week, every morning when I turn on the car the RPM spikes to 2000 then drops to 0. Car stalls. Had my DME updated last year because I had rough idle issues. It takes multiple starts to get it to turn on. After that the car is fine. Hope it's something simple and I already scheduled an appointment with BMW BH.

Had to get AAA to jump car. He tested the battery. And he said low or no voltage. He mentioned it might be the alternator. Hopefully my car lasts until Monday.

[bNks334]

sounds like an un-related issue to the OP. You shouldn't bank your car starting tomorrow though.

[hongsc]

Originally Posted by bNks334

sounds like an un-related issue to the OP. You shouldn't bank your car starting tomorrow though.

Yeah not sure either. Will have AAA jump my car a couple of more times before dropping it off at the dealership.

[chris82]

I've had the rough idle before with my N51. I had around 30k miles on it at the time. It happened in the winter when the temperature was going from super cold to super warm (might have had something to do with it). I had a speed shop check codes and it had misfired. They drove it around and everything was fine. At 37k now and never had this problem again. knock on wood!

[Tim603]

Originally Posted by markus037

i have had issues with cyl 4 5 and 6 misfires a few weeks back but the codes never returned. i was thinking eccentric shaft sensor too, what is the way to check it? plugs were replaced 6k ago with OEM plugs. no oil leaks either. ill have to try cleaning the maf and seeing what happens. air filter was replaced not too long ago either.

This could be related to your 02 sensors. I had an issues with my secondary 02 sensor and it misfired those same cylinders

I would be interested to hear more about this bulletin

[markus037]

im dropping the car off tomorrow to get the vanos bolt recall performed. ill ask them about it. maybe it will be warranty since technically that would be emissions related. the cel did not come back on in about 1400 miles. but im wondering if there is a software issue.

[markus037]

having the software updated tomorrow and then seeing what happens. the service advisor said its a 50/50 shot but we will see.