Engine rattle? Check DISA Valve

nlink720 · 04-04-2010, 04:12 PM

Check your DISA valve if your car has any rattling from the engine bay.

For those who already know this, it is a reminder. For those who do not, the DISA valve is on the M54 engine, and others, and modulates the air stream into the engine manifold.

Unfortunately, the original design was poor, with a pin that can fall out and damage the engine beyond the point of practical repair.

I have 64,500 miles on my car, and noticed in the past couple hundred miles that my engine was rattling in a way I had not heard before -- it sounded like it was getting old, and not maintained the way I have been maintaining it, so I investigated.

To check, you can start the engine, and then disconnect the DISA electrical sensor right next to the valve, and see if the engine gets quieter / rattling stops. This was the case for me, so I removed the unit (very easy) and noticed that the notorious pin was nearly the same as in the thread below. I am sure that it could have come loose at any time and ended my Z4 times.

Links:

http://www.bimmerfest.com/forums/sho...d.php?t=342569

YouTube video of the unit on an E46 (same as ours)

bimmertt · 09-13-2011, 08:26 PM

anyone know what this part # is and if it applies to my 06 z4 3.0si?

revs jump at idle and the engine shakes during low rpms.

RevsPlease · 09-14-2011, 11:27 AM

Quote:

Originally Posted by bimmertt

anyone know what this part # is and if it applies to my 06 z4 3.0si?

revs jump at idle and the engine shakes during low rpms.

Not sure what the PN is but BavAuto has then last time I checked. Turner probably does too. I'm also pretty sure then n52 doesn't suffer any of the problems associated with the m52.

About your car; do you know for sure that your Vanos seals are good?

bimmertt · 09-14-2011, 07:59 PM

Quote:

Originally Posted by RevsPlease

Not sure what the PN is but BavAuto has then last time I checked. Turner probably does too. I'm also pretty sure then n52 doesn't suffer any of the problems associated with the m52.

About your car; do you know for sure that your Vanos seals are good?

how would I go about checking the vanos seals? the problem has surprisingly gone away...for now. thanks in advance.

RevsPlease · 09-14-2011, 11:17 PM

Quote:

Originally Posted by bimmertt

Quote:

Originally Posted by RevsPlease

Not sure what the PN is but BavAuto has then last time I checked. Turner probably does too. I'm also pretty sure then n52 doesn't suffer any of the problems associated with the m52.

About your car; do you know for sure that your Vanos seals are good?

how would I go about checking the vanos seals? the problem has surprisingly gone away...for now. thanks in advance.

Well you can't know for sure without pulling the Vanos unit. On the m54 tell tale signs that your Vanos seals are going bad include bucking and surging under medium throttle between 3K-4K rpm.

Now that Ive thought about it all day your problem sounds like a failing coilpack(s?) or spark plug. No worries about either of those. Easy fix.

FiascoJ · 02-22-2012, 02:57 PM

Thanks for posting this OP. I have this same problem at 63k.

Shipkiller · 02-22-2012, 03:17 PM

The si motor does not have this issue.

BMW never acknowledged the Vanos seal issue but the M54 Vanos seals were changed in the MY 2005+ engines.

G80indy · 02-23-2012, 04:34 AM

observing all that gunk on the old one, how does that happen?
i assume lack of oil changes is part of it, but is that area just basically exposed to air flow only?

Shipkiller · 02-23-2012, 06:08 AM

Lack of oil changes is not the issue. Two things cause the carbon buildup in the intake. Blowby, which is captured by the PVC system and brought into the engine intake and burned and every time you stop your motor, a little bit of exhaust gas's seep back into the intake runners.

All of this, over a long period of time causes buildup in the entire intake system. This is one of the reasons I use Seafoam to clean the intake system.

04-04-2010, 04:12 PM	#1
nlink720 Second Lieutenant 20 Rep 231 Posts Drives: 2004 BMW Z4 Roadster Join Date: Jan 2008 Location: Maryland iTrader: (3)	Engine rattle? Check DISA Valve Check your DISA valve if your car has any rattling from the engine bay. For those who already know this, it is a reminder. For those who do not, the DISA valve is on the M54 engine, and others, and modulates the air stream into the engine manifold. Unfortunately, the original design was poor, with a pin that can fall out and damage the engine beyond the point of practical repair. I have 64,500 miles on my car, and noticed in the past couple hundred miles that my engine was rattling in a way I had not heard before -- it sounded like it was getting old, and not maintained the way I have been maintaining it, so I investigated. To check, you can start the engine, and then disconnect the DISA electrical sensor right next to the valve, and see if the engine gets quieter / rattling stops. This was the case for me, so I removed the unit (very easy) and noticed that the notorious pin was nearly the same as in the thread below. I am sure that it could have come loose at any time and ended my Z4 times. Links: http://www.bimmerfest.com/forums/sho...d.php?t=342569 YouTube video of the unit on an E46 (same as ours) __________________ FS: Leather Recaro Pole Position Seats & Hardware
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09-13-2011, 08:26 PM	#2
bimmertt Lieutenant Colonel 93 Rep 1,794 Posts Drives: 2007 e92 335i Join Date: Nov 2008 Location: Earth iTrader: (7)	anyone know what this part # is and if it applies to my 06 z4 3.0si? revs jump at idle and the engine shakes during low rpms. Last edited by bimmertt; 09-13-2011 at 08:34 PM..
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02-22-2012, 02:57 PM	#6
FiascoJ Enlisted Member 6 Rep 38 Posts Drives: 2003 BMW Z4 3.0i Join Date: Dec 2007 Location: Hermosa Beach, CA iTrader: (0)	Thanks for posting this OP. I have this same problem at 63k.
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02-22-2012, 03:17 PM	#7
Shipkiller Colonel 187 Rep 2,138 Posts Drives: Me Join Date: Oct 2007 Location: Virginia Beach iTrader: (3) Garage List 2008 BMW Z4M Coupe [8.50] 2003 BMW Z4 Roadster [8.33]	The si motor does not have this issue. BMW never acknowledged the Vanos seal issue but the M54 Vanos seals were changed in the MY 2005+ engines.
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02-23-2012, 04:34 AM	#8
G80indy Save the Manuals 1714 Rep 2,937 Posts Drives: Z3, E46, G80 Join Date: May 2005 Location: Indy iTrader: (0)	observing all that gunk on the old one, how does that happen? i assume lack of oil changes is part of it, but is that area just basically exposed to air flow only? __________________ 2023 G80 6MT, CCBs 2002 330i Dinan, 5MT 2000 Z3 Conforti, 5MT
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02-23-2012, 06:08 AM	#9
Shipkiller Colonel 187 Rep 2,138 Posts Drives: Me Join Date: Oct 2007 Location: Virginia Beach iTrader: (3) Garage List 2008 BMW Z4M Coupe [8.50] 2003 BMW Z4 Roadster [8.33]	Lack of oil changes is not the issue. Two things cause the carbon buildup in the intake. Blowby, which is captured by the PVC system and brought into the engine intake and burned and every time you stop your motor, a little bit of exhaust gas's seep back into the intake runners. All of this, over a long period of time causes buildup in the entire intake system. This is one of the reasons I use Seafoam to clean the intake system.
	Appreciate 0 Quote