[nozydog]

B58 is my first ever 6 pot BMW and although only picked up 5 weeks ago my first impressions are very positive! The only slight disappointment is that idling when fully warm, i am really aware of the engine running as the car shudders slightly! Not excessively, but when I owned my e90 (148hp) & e92 (170hp) 4 pots, there were many occasions when I hit the start button to turn on the engine, only to find I'd just turned it off because it was already running... those engines were so smooth at idle that when waiting for someone to get in the car, I'd forget I'd already started up!!

Is this normal, maybe just because it is so much more powerful an engine? I've always understood that a six should run smoother than a four!?

it is totally smooth on the move!!

[jalkster]

Originally Posted by nozydog

B58 is my first ever 6 pot BMW and although only picked up 5 weeks ago my first impressions are very positive! The only slight disappointment is that idling when fully warm, i can really feel the engine causing the car to shudder slightly! Not excessively, but when I owned my e90 (148hp) & e92 (170hp) 4 pots, there were many occasions when I hit the start button to turn on the engine, only to find I'd just turned it off because it was already running... the engine was so smooth at idle!! Is this normal, maybe because it is such a powerful engine? I've always understood that a six should run smoother than a four!?

Mine is the same way.

[DrifterX]

I haven't noticed any shudder on my car since I got it. How warm does the weather need to be for you to notice?

It could be that the other cars you've had idle at a higher RPM so they seem smoother. Lower RPM can introduce slight harmonic vibration or shudder as you may call it.

[peteyfresh12]

Originally Posted by nozydog

B58 is my first ever 6 pot BMW and although only picked up 5 weeks ago my first impressions are very positive! The only slight disappointment is that idling when fully warm, i am really aware of the engine running as the car shudders slightly! Not excessively, but when I owned my e90 (148hp) & e92 (170hp) 4 pots, there were many occasions when I hit the start button to turn on the engine, only to find I'd just turned it off because it was already running... those engines were so smooth at idle that when waiting for someone to get in the car, I'd forget I'd already started up!!

Is this normal, maybe just because it is so much more powerful an engine? I've always understood that a six should run smoother than a four!?

it is totally smooth on the move!!

I get the same as well. Definitely on the cold start. Even when it warms up and waiting for someone or at a light, it'll shudder sometimes. I look at as the car shaking from all the power

[nozydog]

Originally Posted by DrifterX

I haven't noticed any shudder on my car since I got it. How warm does the weather need to be for you to notice?

It could be that the other cars you've had idle at a higher RPM so they seem smoother. Lower RPM can introduce slight harmonic vibration or shudder as you may call it.

Well at the moment temperatures here are between 10 & 15 degrees Celsius, so fairly cool but not cold! I did wonder whether my older cars had higher idle speeds, this car seems to idle at around 650 which is pretty low! The issue (which may not even be an issue) doesn't particularly bother me, in fact it's nice to know the engine is running! Just assumed it would idle more smoothly than my old four pots!

[RedKloud]

Mine does it on a cold start only.

[DrifterX]

Originally Posted by nozydog

Well at the moment temperatures here are between 10 & 15 degrees Celsius, so fairly cool but not cold! I did wonder whether my older cars had higher idle speeds, this car seems to idle at around 650 which is pretty low! The issue (which may not even be an issue) doesn't particularly bother me, in fact it's nice to know the engine is running! Just assumed it would idle more smoothly than my old four pots!

It's quite the torquey motor as I'm sure you already know, it probably doesn't need much to keep it idle.

I understand your view but Germans hate idling so I bet they want to keep gas consumption as low as possible - just enough to keep it purring without wasting gas. 650 RPM idle is definitely low but it's normal for this engine

My previous car had a 4 pot but it was a low revving NA engine (less than 7,000 RPM redline) but had the same amount of torque as it had hp (155hp/152ft-lb)... it would idle as low as 550 RPM sometimes lol

[nozydog]

Originally Posted by DrifterX

It's quite the torquey motor as I'm sure you already know, it probably doesn't need much to keep it idle.

I understand your view but Germans hate idling so I bet they want to keep gas consumption as low as possible - just enough to keep it purring without wasting gas. 650 RPM idle is definitely low but it's normal for this engine

My previous car had a 4 pot but it was a low revving NA engine (less than 7,000 RPM redline) but had the same amount of torque as it had hp (155hp/152ft-lb)... it would idle as low as 550 RPM sometimes lol

I certainly do, I'm still running in at the mo as I'm nearing 1000 miles, but I can feel the potential under my right foot and I can't wait to push it all the way to the floor!! It has over 50% more torque than my previous car, a 6 pot NA Cayman! In a way it's quite nice feeling that rumble at idle, reminding you of the potential under the hood!

[Wires]

The issue is it runs REALLY lean all the time. That "lumpy" idle is just a bi-product of the ECU trying to maintain idle at an AFR that an engine should never run at.

Perfectly normal. My 2008 GMC does the same. I don't remember my n54 having as much shutter though, but I believe it ran a bit richer than the B58 does.

[TurboM]

Originally Posted by Wires

The issue is it runs REALLY lean all the time. That "lumpy" idle is just a bi-product of the ECU trying to maintain idle at an AFR that an engine should never run at.

Perfectly normal. My 2008 GMC does the same. I don't remember my n54 having as much shutter though, but I believe it ran a bit richer than the B58 does.

There are so many factors that go into the "smoothness" of idle such as ignition timing, cam timing, AFR, RPM, injector pulse, rotating assembly weight, motor mounts, etc. This really has nothing to due with the size or power of an engine. There are other variables that could contribute as well. To put it in simple terms, pretty much any modern engine can idle as smooth or as rough as you want it to, its just a matter of what the computer tells it to do.

[paul e]

Originally Posted by nozydog

Well at the moment temperatures here are between 10 & 15 degrees Celsius, so fairly cool but not cold! I did wonder whether my older cars had higher idle speeds, this car seems to idle at around 650 which is pretty low! The issue (which may not even be an issue) doesn't particularly bother me, in fact it's nice to know the engine is running! Just assumed it would idle more smoothly than my old four pots!

650 seems low. Very low.

[Mr.G20 M340]

Unfortunately the lumpy idling is the only downfall of the B58 engines, It only happens when the car is cold so it shouldn't be that big of a worry. I hope they fix this issue with updates for the transmission hopefully.

[PeterA90]

It's a high compression motor that runs lean. It will be more pronounced on cold start. Lumpy idle at that time is normal. Even at operating temps the idle will shake here and there because the car is trying to main a certain a/f ratio (much harder to do when ambient temps are low). If you have no codes/cel, don't lose sleeep over it.

[Kennybar112]

I notice really lumpy idle one cold starts. Would happen for 10-15 seconds during the same interval on start up. Shakes the car side to side. Read up its normal but seems odd...

[rockymtnpilot]

Thank you, all of you motor nerds. I've been curious about this since I had my E60

[nozydog]

Originally Posted by rockymtnpilot

Thank you, all of you motor nerds. I've been curious about this since I had my E60

Your E60 does/did it too?

[riskmaker76]

Funny... my new 440 is smooth as butter even when cold... shock how smooth it is... has mppsk though

How you all break in the motor? I drive like I stole it right out the dealer...

[jalkster]

Originally Posted by riskmaker76

Funny... my new 440 is smooth as butter even when cold... shock how smooth it is... has mppsk though

How you all break in the motor? I drive like I stole it right out the dealer...

I planned on doing a 1500 mile break in but the dealer told me that it is not needed and that they "come broken in from the factory".

[bimmer456]

Originally Posted by nozydog

B58 is my first ever 6 pot BMW and although only picked up 5 weeks ago my first impressions are very positive! The only slight disappointment is that idling when fully warm, i am really aware of the engine running as the car shudders slightly! Not excessively, but when I owned my e90 (148hp) & e92 (170hp) 4 pots, there were many occasions when I hit the start button to turn on the engine, only to find I'd just turned it off because it was already running... those engines were so smooth at idle that when waiting for someone to get in the car, I'd forget I'd already started up!!

Is this normal, maybe just because it is so much more powerful an engine? I've always understood that a six should run smoother than a four!?

it is totally smooth on the move!!

It definitely has an awesome sounding exhaust note on cold start and maybe a little vibration could that be it? Also, larger displacement engines may have vibrate a little more. On my B58, when it is warmed up and idling at 700 RPM I believe the exhaust is partially close and it idles smooth. So quiet that I forgot to turn it off one time! The comfort access still allows you to lock the door with the engine running, which I did, but it doesn't chirp. So I noticed that and saw that the engine was till running. The exhaust note could still be heard but it is quieter.

[rockymtnpilot]

Originally Posted by nozydog

Your E60 does/did it too?

Yessir

[Frank Richardson]

I was disappointed in the rough idle. Not all that bad, but it bothered me. Had the Dinan stage 1 installed and I don't notice now. Seems to run smoother at idle.

[F82Tazmanian]

I never had a rough idle, but I did notice a weird sensation. When I'm cruising around town at 50-60mph and press the throttle just enough to sit at 1500-2000 and not have the car downshift, I notice an obvious hesitation and the rpms fluctuate. Anyone notice this? It's very subtle.

Just bought it last week, 250 miles on the clock.