[stopper]

Hey folks, please take a look at this video I took today of my car idling in my driveway. Its an n54 335xi.

On and off for the past month or so, I've noticed this periodic droning sound coming from my engine bay for a few seconds at a time. It sounds similar to some type of pump cycling on and off. My car isn't generating any fault codes and it seems to drive just fine, but this noise is new as far as I can tell and it's freaking me out. I only hear this when the car is sitting at idle.

It sounds like its coming from the top side of the engine, not down under the block. It's on the turbo side of the car, right in the middle of the block (front to back) Does anyone have any idea what's going on here?!

https://youtu.be/uwsV5ChwehY

**If it helps, within the past 5000 miles the car has: new spark plugs, new ignition coils, new silicon vacuum lines, new intercooler, new charge pipe, new water pump, new thermostat, new RB PCV valve. Within the past 10000 miles: new injectors, new oem turbos.

[V.I.335is]

Sounds like your boost solenoids.. From info gathered throughout the forums they seem to buzz when there going bad..

[stopper]

Hmm thanks for the tip. Looking at some other youtube videos about boost solenoids, that may be the culprit.

I don't have the time to splice my vacuum lines, install a T-fitting with a gauge and a pump and test the integrity of each solenoid, so I just ordered 2 of these instead and we'll see if that solves it.

https://www.fcpeuro.com/products/bmw...id-11747626350

I'll update the thread on the results!

[Banana Clipper]

Def boost solenoids, mine have same noise. You can confirm by removing vacuum line from canister and it will stop

[stopper]

Just popping in to update this post in case anyone else runs into this issue.

Status: FIXED.

Thanks for pointing me in the right direction guys. I replaced the two boost solenoids with the ones in my link above and the noise stopped completely. The car is running great!