[Jarrod]

retracted, I was listening to the wrong sound.

I agree with others that it's probably a clearance issue with you DPs.

[NoQuarter]

Originally Posted by Holtdahooligan

Are you referring to the motor mounts being shot? I just last month installed the Ad engineering motor mounts. The car made the same noise before and after.

Fair enough. But the engine still moves with new motor mounts.

[Vincent_E90]

Mine was the downpipes rattling against the subframe FYI.

[ajbmw311]

I have had the exact same sound on deceleration for the past 7-8 months. It happens most noticeably when engine is cold. It's still there but not super loud/noticeable once engine is at normal operating temps.

To me it sounds like Vanos area or valve ticking, like it's right on top of the engine and it is most definitely not coming from the drivetrain. I am running stock DP's, VSRF FMIC, JB4 and intake. I've tried replacing intake with stock airbox as well as inspected timing chain and other internals visually when I replaced my valve cover gasket some 5 months ago. I'll try to post a video when I start it up on my way home from work.

[ajbmw311]

Here's the sound on my car after I left work today

[aerolland]

Has anyone made any progress on this deceleration noise problem? Mines been doing it for some time, very similar to what has been posted via video. Just installed catless DPs and noise is still there, don't think I have any frame touching though. Could Vanos system be making noise as suggested above?

What's odd for me is while noise us present, if you clutch it the noise stops. Let clutch out and it begins again right where it left off.

[N54_ABQ]

I have been having the same decel noise for more than 6 months now. No performance loss or codes of any kind! I've been throwing parts at it left and right trying to address this "Deceleration Rattle."

Items I've changed with new genuine BMW parts trying to fix this sound;

Chain tensioner
VANOS Solenoids
Non-Return Valves
High Pressure Fuel Pump
Vacuum Pump
Oil Pump

There was no change in sound after changing any of these parts.
I finally watched the data through MHD manual logging and the sound ONLY starts when Intake VANOS actual position goes to -130 degrees. If I touch the throttle at all VANOS comes back on and the sound stops.

Just bought a cam alignment tool and a new Intake VANOS actuator/sprocket.
I'm going to look at everything under the valve cover this weekend hoping something will show wear or malfunction of some kind.
I'll let you guys know what I find.

[N54_ABQ]

I finally figured it out!! The cam timing was off!

I put the flywheel pin in to lock at TDC. Went to put the cam blocks on and wasn't even close. I double checked I was at TDC by verifying No.1 piston was at max height. Loosened the sprocket bolts and turned the cams until the tool slid on. Re-tightened sprocket bolts, removed flywheel pin and turned over by hand a couple revs back to TDC. Put the flywheel pin back in and alignment blocks slid on as expected.

I decided to look at everything while I was in there. All the cam journals looked fine. The steel oil sealing rings hadn't grooved out the ledges yet. Installed the new teflon rings and looked at every lifter/roller. All looked great. Re-assembled at the correct timing and the sound is GONE!!

I never had any VANOS or timing related codes or power loss. There was no evidence that the sprockets slipped on the cam faces and all the chain guides looked fine. Both intake and exhaust sprockets were off the same amount. And both impulse sending wheels were lined up with cam correctly, meaning that if I moved away from TDC both tools would have lined up. Either an unqualified tech did not set the timing correctly or the chain jumped a couple teeth. I may never know...

My guess as to what exactly was making the noise is that the DME requests a certain cam degree by activating the VANOS actuators via the solenoids until the cam position sensors read the degree that is requested. If timing is off the VANOS actuators are completely maxed out to reach the requested degree making them rattle. That's my best guess. If anyone has another theory as to why my timing was off and where the noise actually comes from I'd love to hear.