[maswastage]

I have a request for my fellow 335d drivers. Could you guys check to see if your engine makes a sort of whistling or beeping noise at idle from the front right side of the engine compartment?

I noticed this noise the other day because it was quite loud and audible even from a distance. Ever since then I've heard the noise every time I park my car from a trip and let it idle for a few seconds, only now it seems much fainter and less audible. You can only hear it from outside the car, and it's not linked to engine RPM.

The thing is I'm not sure if this is normal or not. So if anyone else can check that would be helpful. It's best described as a beeping noise, identifiable as more of a whistling or squeaking if you really stick your head in the engine bay, and it "beeps" randomly, almost like Morse code. I took a video of the noise but the sound quality isn't great, and I won't be able to upload it until later.

Thanks, and hopefully I'm just being paranoid.

Alright here's the video; like I said the sound quality is pretty bad but you should be able to hear the beeping in the background. The recording seems to focus on the engine rather than the beeping; in person it's a bit louder and easier to hear.

I have no idea what it is. But if it turns out other cars are making the same noise I would have to assume it's normal, and ease my mind.

[Thud]

Whistling and beeping? Like this?

[HoustonScott]

I have never heard any sounds like you describe. However, when the car is shut down I can hear sounds like electric motors running or turning on and off from the passenger side front of engine bay. Electric sounds when the car is off under the hood but very faint, discovered while detailing engine bay. Any ideas what whats going on. I suspect that cooling of the turbo continues after shut down. But I don't know I am only guessing.

HS

[maswastage]

I added the video. Again, it's not the best quality but you should be able to make out the beeping in the background.

And Scott, electric noises after the car is off are 100% normal. There are various electronic systems that don't fully shut off until quite some time has passed after turning off the car.

Now as for this beeping, it has me stumped.

[Neutrinolad]

No sounds from mine.

[HoustonScott]

I think I hear what your talking about just after the rpm goes up a bit. The only thing I can think of is that the partial filter that burns off every so often may have come on while you were at idle and just happen to be listening. The power draw may account for the rpm increase and the electrics to heat up the filter is the noice your hearing. My guess but a good one...

HS

[maswastage]

Ah I should clarify a few things. The change in volume in the video isn't from me revving the engine, it's from me moving the camera closer to the engine. In fact it's at idle the entire time. I too thought it might be something to do with the particle filter cleaning itself, but I've heard it after every trip I've made since then. It's pretty faint now, but I can definitely still hear it.

[samwoo2go]

if it goes "whooooop whooooop." I think I know what the problem is

[vasillalov]

I hear the same thing on my 335i

[F32Fleet]

I'm not able to listen to the audio, but I can say that my D gives off a beep or continuous beep after I shut it off. Now the whistling noise, which I hear when the engine is cold, I'm fairly certain is one of the turbos. TBH I've thought nothing of it.

[DnA Diesel]

MW, I don't get that from mine, at least not that I've heard. Sorry I can't help...

[Ron1n]

Nor mine, unfortunately..and God bless the padding underneath that hood..rofl

[DnA Diesel]

Originally Posted by Ron1n

Nor mine, unfortunately..and God bless the padding underneath that hood..rofl

LOL

For a second, I was going to ask "are you sure that's a 335d?"

[maswastage]

Thanks for checking guys, although I'm a bit disheartened now that something may be out of whack with my car. I guess it's one of those things I have to keep an eye on, or in this case an ear.

[Quasimodem]

I listened to the video, don't hear any beeping, just a diesel engine chugging along.