[xavb]

So the car recently started making this noise. Probably about over the last month. Last week got significantly louder. I was able to take a video of the noise. It doesn't start making the noise though until the car is warmed up...well until driving the car for about 30-45 minutes (way to work or home). I'm not using the brakes when it happens, starts on slight acceleration (between 15-25 MPH), and then will quiet down as the rpms come down. Mods on the car are JB4 PnP, BMS DCI, and VRSF downpipes. Its at BMW right now and they are trying to figure out what it is but looking to see if anyone else has experienced this since even with the video I provided and after telling them that it doesn't happen until the car is warm, they said they couldn't duplicate the problem.


I apologize for the shaky video -

[BlackBB6]

Try removing the brake pad sensor on the front driver side and see if it continues. I had a similar noise and the dealer said it was the pad wear sensors.

[xavb]

Was your car making the noise even when not braking?

[midiman369]

I have that exact sound! Only after car is warm and driven for over 15 minutes. {Brakes not being applied this is during acceleration!}

Mine's not as bad though, it only seems to happen when turning left from 0-15mph, like when I am driving in a parking lot. I just had my car completely checked by the dealer, they were having a free inspection promotion, and had some routine maintenance done and they didn't find anything wrong with the car. I did not mention the sound to them at the time though.

I've heard that it could be the steering column needing to be greased, or simply brakes need maintenance/repair, also I think there's an SIB about the pad wear sensor being the culprit of this sound. I'm bringing my car in to get an LSD in the next few weeks and I'll have my mechanic check it out again...

Let us know if you find out anything.

EDIT: sorry for repeat info, started writing this reply before any other responses were posted.

[xavb]

Will do...the advisor told me yesterday that they might need the stock parts to be able to diagnose it and that they might have to charge me for the diagnosis if it ends up not being covered under warranty. Hope its covered, I bought the car used and it only has about 1000 miles left of BMW pre-owned warranty. I'll mention the brake pad sensor to them.

Thanks for the input guys.

[Jeff@TopGearSolutions]

My first guess was something in the brakes but what exactly im not sure.

[lawwailok]

probably your brake sensor. i had a similar noise twice and my SA immediately told me, "yea it's the brake sensor, we'll take care that" when my car was under warranty. after the 2nd time fixed, i went with Brembo BBK, since then never heard that noise again, hahahahaha

that's a pretty common problem on our brake sensor. it's too sensitive and like to got stuck and make noise.

[xavb]

Still waiting on today's update, but yesterday I did mention the brake sensor issue to them and they stated they were aware of that issue but that they hadn't heard it that loud before so they want to make sure it isn't anything else.

lawailok - u changed out the whole brakes? that was going to be my next thing to look into, if its not fixed with stock brakes, does it go away with an aftermarket setup? if so, I don't mind that haha.

[lawwailok]

Originally Posted by xavb

Still waiting on today's update, but yesterday I did mention the brake sensor issue to them and they stated they were aware of that issue but that they hadn't heard it that loud before so they want to make sure it isn't anything else.

lawailok - u changed out the whole brakes? that was going to be my next thing to look into, if its not fixed with stock brakes, does it go away with an aftermarket setup? if so, I don't mind that haha.

well the BBK upgrade doesn't allow to use the brake sensor. so there's no need to worry about it. down side, you have to measure the brake pad yourself to determine when is the pad needed to be changed.

[Jeff@TopGearSolutions]

^ Looks good!

[BMWM.D.]

That doesn't sound like a brake pad wear sensor to me. Could be some type of noise from the brakes (pad/rotor contact), though. Does it go away if you apply a little brake pressure with your left foot while you maintain the speed where it occurs?

Are your brake pads and rotors OEM?

[xavb]

The noise does not go away when applying the brakes. It only goes away when I get up to about/over 30 or at a complete stop. Otherwise, once the car is warm and you start giving it gas it starts and is louder around 20mph. Front brakes are not stock (took it in to have the front brakes looked at before and BMW told me they were not stock brand; don't know what brand though as they were on the car when I bought it and it was used); rears I believe are stock.

[usc335]

My car made that sound for years. I had Cool Carbon pads for what it's worth. I just changed my pads and rotors (all stock) and now the noise is gone.

[psmitty95]

Maybe this?

http://www.e90post.com/forums/showthread.php?t=697365

[xavb]

So this is what they did for the noise...

"Verified noise, coming from valve cover, oil separator torn inside valve cover, removed ignition coils, removed fuel rail, removed wiring harness, removed and replaced complete valve cover"


What is the oil separator?