Hi all, I have a 2004 530i and I get a high pitched whistling sound when I accelerate. It can only be heard when the windows are down, and only when I accelerate. For example if I'm at a stop and apply throttle to go I'll hear the sound. It appears to be coming from intake - the obvious. The whistle will remain persistent until I hit a normal cruising speed, and will resume if I need to accelerate more until the desired cruising speed is reached. It's kind of annoying and was wondering if anyone knew what could cause this problem. I did a search and came up with various hits, none really described the symptoms I'm having. What do you all think?

Best,
-Jay

 

Also worth mentioning. Today sitting in the driveway with the car running I was revving up the engine to 2K to 3.5K and I didn't hear a thing... Weird.

 

i think its normal.i have it in my car and in my friends 630i. its just how the bimmer sounds like. i find it rather sexy. i wish i can increase that sound. heard headers should do the job

 

Check the cold air intake box. It may have a hole in the plumbing, problem with the air cleaner, or it isn't seated properly.

 

Thanks guys, I'll take a look at some of the hoses - see if there's any dry rot or cracking. I've checked the Air Intake a few times, but I can't say for sure it's actually seated correctly.

Anyone else have some suggestions?

 

If the 530i was turbocharged, I'd say it was the turbo. Sounds exactly like a turbo, down to the not-doing-it-on-your-drive-revving thing. Turbo's can spin at around 100000rpm, so whistle quite nicely.

You've not accidentally swapped your car for a 535i have you?

 

Yip sounds like a turbo to me, its normal and sounds cool

 

how come i have that sound on my 520, 2.2L I6 and my friend's 630i 3.0L I6

We both have it, i think its the sound of the exhaust.its just the way it is. NO???? My friend increased that sound by adding headers on his 630i

 

I don't believe the car has a turbo - I mean it's just a 2004 with a early build date of October. I suppose another way of describing the noise would be like that of squeaky brakes, but only happens when I'm on the go. If it's normal I'm fine with it, but if it's not then obviously I'd like to address it.

 

Were you able to resolve your whistling issue ?
I have the same problem as you describe, also from a 2004 530i.