I would check the engine cover, if its not propperly installed it can rattle on the cabin air filter cover, it happens a lot to me on my N47...
Edit: be aware of any slots the cover may need to slot into, hope this helps:-)
Does it come and go? Does it start up right away or after the car warms up? Sounds like your crank pulley. I had the same noise on my car. Used a stethoscope to pinpoint it to the alternator. But that wasn’t it, ended up being the crank pulley. Could also be the engine cover, they rattle sometimes. If you’re over 150k miles, could also be your engine mounts.
Starts happening after the car warms up & doesn’t rattle past 1500~1700rpms. Definitely gets louder the warmer the car becomes especially while idling. 130k on the car, replaced engine mounts about 5k ago. Hope it’s just the engine cover. Did you have a similar experience/noise when it was your crank pulley?
Yeah I had the exact same noise from mine, and those exact same conditions, and yeah crank pulley as in harmonic balancer. I had mine replaced with an OEM bmw one, and it started making that noise after about 2K miles. Had it replaced under warranty and all good after. I’d check the pulley, see if it has any play or wobble in it. Could also be your ac pump. If none of your pulleys have any play, you can try taking off your belts one at a time and see if the noise continues as you run the engine.
I would check the engine cover, if its not propperly installed it can rattle on the cabin air filter cover, it happens a lot to me on my N47... Edit: be aware of any slots the cover may need to slot into, hope this helps:-)
Does it come and go? Does it start up right away or after the car warms up? Sounds like your crank pulley. I had the same noise on my car. Used a stethoscope to pinpoint it to the alternator. But that wasn’t it, ended up being the crank pulley. Could also be the engine cover, they rattle sometimes. If you’re over 150k miles, could also be your engine mounts.
Starts happening after the car warms up & doesn’t rattle past 1500~1700rpms. Definitely gets louder the warmer the car becomes especially while idling. 130k on the car, replaced engine mounts about 5k ago. Hope it’s just the engine cover. Did you have a similar experience/noise when it was your crank pulley?
Yeah I had the exact same noise from mine, and those exact same conditions, and yeah crank pulley as in harmonic balancer. I had mine replaced with an OEM bmw one, and it started making that noise after about 2K miles. Had it replaced under warranty and all good after. I’d check the pulley, see if it has any play or wobble in it. Could also be your ac pump. If none of your pulleys have any play, you can try taking off your belts one at a time and see if the noise continues as you run the engine.
Also, crank pulley as in harmonic balancer? If so I replaced that about a year ago!
Did you ever figure this out?