How smooth is your idle

Derekz4 · 11-25-2019, 10:11 PM

I posed this question to another member on his 640. How smooth is your idle to the seat of your pants?
I've noticed that mine is a little shaky when I first fire it up on occasion then smooths our after 5 seconds or so. It's still not as smooth as my M54 I have in my 03 Z4 though.
How about yours?

Shawn M · 11-26-2019, 07:50 AM

Quote:

Originally Posted by Derekz4

I posed this question to another member on his 640. How smooth is your idle to the seat of your pants?
I've noticed that mine is a little shaky when I first fire it up on occasion then smooths our after 5 seconds or so. It's still not as smooth as my M54 I have in my 03 Z4 though.
How about yours?

That's a great question as I've wondered it myself. I also get the occasional "shimmy" when I first start my '16 640i. I just recently had it happen with a bit more force and then the next time I turned on my car my engine light appeared. Took it to the dealer to find that I had a bad O2 sensor, replaced it.

I do still get a slight shake. I've noticed if I turn off the HVAC it smooths out... which drives me insane that BMW would program it to ALWAYS turn on with the start of the car. I know it can be programmed out...

ezmaass · 11-26-2019, 08:44 PM

Idle is very smooth - very predictable.

thebmw · 11-26-2019, 08:57 PM

Quote:

Originally Posted by ezmaass

Idle is very smooth - very predictable.

Agree. But we have the V8. However I really don't think that should matter. The I6 is a very smooth engine.

JBF650 · 11-26-2019, 11:58 PM

Yes, we are comparing V8’s to 6’s. My V8 is rocksteady, no tremors even on cold start, once warm and fast idle is off, it’s barely perceptible on tick over.
My other BMW turbo 6s were smooth perhaps not as smooth as V8’s but nothing I was ever cognisant of.
If it’s obviously missing and rough then perhaps there is an ignition issue. A occasional cough then even out ....I wouldn’t be too concerned

E92TTCoupe · 11-27-2019, 04:44 AM

So I heard and read that once you do “ walnut blasting “ it becomes smoother..

Russbmw · 11-27-2019, 08:19 AM

Quote:

Originally Posted by E92TTCoupe

So I heard and read that once you do “ walnut blasting “ it becomes smoother..

Correct, although I'd not really expect the intake to need walnut blasting until about 70k-80k miles.

kansasbeachbum · 11-27-2019, 07:42 PM

Quote:

Originally Posted by Shawn M

Quote:

Originally Posted by Derekz4

I posed this question to another member on his 640. How smooth is your idle to the seat of your pants?
I've noticed that mine is a little shaky when I first fire it up on occasion then smooths our after 5 seconds or so. It's still not as smooth as my M54 I have in my 03 Z4 though.
How about yours?

That's a great question as I've wondered it myself. I also get the occasional "shimmy" when I first start my '16 640i. I just recently had it happen with a bit more force and then the next time I turned on my car my engine light appeared. Took it to the dealer to find that I had a bad O2 sensor, replaced it.

I do still get a slight shake. I've noticed if I turn off the HVAC it smooths out... which drives me insane that BMW would program it to ALWAYS turn on with the start of the car. I know it can be programmed out...

I have a 2016 640 GC 55,000 miles. I love the low rumble at idle. No shimmy. Smooth as silk.

E92TTCoupe · 11-29-2019, 02:55 AM

Quote:

Originally Posted by Russbmw

Correct, although I'd not really expect the intake to need walnut blasting until about 70k-80k miles.

True but I read other wise. Stating it all depends how much you drive etc. I would like to get it done soon and see for myself first hand.

thebmw · 11-29-2019, 08:26 AM

Could it be a spark plug issue or a fuel pump issue?

city1991 · 11-30-2019, 01:08 PM

Quote:

Originally Posted by Derekz4

I posed this question to another member on his 640. How smooth is your idle to the seat of your pants?
I've noticed that mine is a little shaky when I first fire it up on occasion then smooths our after 5 seconds or so. It's still not as smooth as my M54 I have in my 03 Z4 though.
How about yours?

Mine idles and drives beautiful

derailed · 12-02-2019, 07:54 AM

70,000 miles on my 650i and when I idle sometimes I forget that I turned the auto start/stop off.

Keithark · 12-03-2019, 02:10 PM

Quote:

Originally Posted by Derekz4

I posed this question to another member on his 640. How smooth is your idle to the seat of your pants?
I've noticed that mine is a little shaky when I first fire it up on occasion then smooths our after 5 seconds or so. It's still not as smooth as my M54 I have in my 03 Z4 though.
How about yours?

If you have vibration through the passenger seat , which I had, it is probably the engine mounts, it's apparently a common problem that is normally misdiagnosed ( tech quote)
Had mine done 640d , cured all the vibes

NorthCountryGuy · 12-03-2019, 02:21 PM

Ditto for the motor mounts.
Had this on the Porsche, and when replaced made a world of difference in the feel of the idle.

11-25-2019, 10:11 PM	#1
Derekz4 First Lieutenant 169 Rep 332 Posts Drives: BMW 640i. BMW Z4,01 Bullitt Join Date: Jun 2019 Location: Southern California iTrader: (0)	How smooth is your idle I posed this question to another member on his 640. How smooth is your idle to the seat of your pants? I've noticed that mine is a little shaky when I first fire it up on occasion then smooths our after 5 seconds or so. It's still not as smooth as my M54 I have in my 03 Z4 though. How about yours?
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11-26-2019, 08:44 PM	#3
ezmaass Lieutenant Colonel 370 Rep 1,698 Posts Drives: '17 650xi GC / '15 Audi R8 V10 Join Date: Oct 2008 Location: CT iTrader: (0)	Idle is very smooth - very predictable. __________________ 2017 BMW 650xi Gran Coupe \| MSport \| Exec Package \| Driver Assist Plus \| ACC Stop & Go \| Adaptive Drive \| B&O \| Night Vision \| Cold Weather \| Active Seats 2015 Audi R8 V10 \| Brilliant Red on Black \| S-Tronic \| Carbon Sideblades \| Carbon Trim \| Full Leather \| Sport Exhaust \| Illuminated Doorsills \| I-Pod \| Contrast Stitching Previous: '14 550xi, '07 335i, '01 325i
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11-26-2019, 11:58 PM	#5
JBF650 Second Lieutenant 116 Rep 248 Posts Drives: 2015 F13 LCI 650i Coupe Join Date: Sep 2019 Location: Sydney Australia iTrader: (0)	Yes, we are comparing V8’s to 6’s. My V8 is rocksteady, no tremors even on cold start, once warm and fast idle is off, it’s barely perceptible on tick over. My other BMW turbo 6s were smooth perhaps not as smooth as V8’s but nothing I was ever cognisant of. If it’s obviously missing and rough then perhaps there is an ignition issue. A occasional cough then even out ....I wouldn’t be too concerned
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11-27-2019, 04:44 AM	#6
E92TTCoupe Major 145 Rep 1,493 Posts Drives: x335i/x550i/x640i/x540i/c750i Join Date: Oct 2012 Location: New York iTrader: (7)	So I heard and read that once you do “ walnut blasting “ it becomes smoother..
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11-29-2019, 08:26 AM	#10
thebmw Post Advisor 1631 Rep 1,693 Posts Drives: More Manuals than Automatics Join Date: Feb 2010 Location: Illinois iTrader: (10)	Could it be a spark plug issue or a fuel pump issue?
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12-02-2019, 07:54 AM	#12
derailed Experienced User 7 Rep 29 Posts Drives: bimmaghini Join Date: Nov 2019 Location: gary, indiana iTrader: (0)	70,000 miles on my 650i and when I idle sometimes I forget that I turned the auto start/stop off.
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12-03-2019, 02:21 PM	#14
NorthCountryGuy The Quiet One 1711 Rep 624 Posts Drives: M6, E70, E71 Join Date: May 2019 Location: I’m right here... iTrader: (0) Garage List 2013 X6 M [0.00] 2013 M6 [0.00] 2013 X5 LCI 35i Spo ... [0.00] 2013 X5 LCI 35i [0.00]	Ditto for the motor mounts. Had this on the Porsche, and when replaced made a world of difference in the feel of the idle. __________________ 2013 M6 Coupe Sakhir Orange Metallic / Sakhir Orange \ Black Merino - The Prince 2013 X5 LCI 35i Jet Black / Black SensaTec - The Horse 2013 X5 LCI 35i Space Grey Metallic / Black Nevada // Sport Pkg - Daughter’s 2013 X6 M Sapphire Black Metallic / Black Merino \ Carbon Fiber - Son’s
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