WTF is this noise? PLEASE HELP
 

2008 335XI

I took my car for a drive last night, got home to put in the garage and heard this. Notice that the noise STOPS for a little (middle of the video) and starts again.

It is louder than the noise on cold start and this was after my car was fully at temp and had been on the road for 40-60 minutes.

I'm under new car warranty still (2 weeks left ONLY) and have CPO...

http://www.flickr.com/photos/7602554...in/photostream

TIA

Take it to the dealer ASAP before your warranty runs out.

Could be the belt slipping off and/or hitting something (did you check if its firmly on the arm?) could also be your water pump.

Hard to know for sure, regardless, drive into your dealership ASAP and tell them you are scared to drive it due to safety reasons and have them look it over. Things like water pumps cost $$$

And considering you have a 335i, its could be a 1 of a million things to do with your turbos...

PS: Take full advantage of your warranty almost ending and have them do a full inspection on the car, have them catch anything before its too late. Just my opinion though.

Mine too... but the SA that I spoke to said they don't do that. I can't believe that they don't... it's good for them (dealership) and me too. The SA said that it's frowned upon by BMW head-office and they get suspicious of 'warranty shopping' --- but give me a break; doesn't everyone running out of warranty do this? Disappointed. If anyone knows a 'more friendly' SA or dealership in GTA please LMK.

...oh and I'm also disappointed that this is only 6 days after picking up a car that was part of their "certified pre-owned" -- so they certified it and I had lifters go less than 1000KM later? I am trying to beat on this a little before my new car warranty is up... been going out every night so far... still can't get pathway lighting to work.

Sounds like its the AC pulley, the electromagnetic one, It gets noisy when worn or dirty when the ac switches on and quiet when it switches off. Was your blower set to window defog? If yes, then its the ac system and thats exactly what it sounds like

So to test this I should be able to turn my AC on, set to window defog? I don't know why it would go off then back on in such a short time?

...and I'm reading 'worn or dirty'... should be replaced I guess... is this something that the dealership can see easily.... I'm getting ready to put on my fighting gloves...........

Well, when you switch front window defog on ( blower to the front window), the ac comes on automatically. If you just switch the AC on, make sure the fans are on too ( blower fans) and it SHOULD make the same noise.

The AC compressor does not run a lot, it switches on and off, depending on AC system load. If its truly the AC pulley ( which is magnetic) it either bypasses the compressor or actuates it, it will make the noise whenever the compressor works. I've heard much louder, yours is actually quiet lol, some SQUEEL like mad because they are either siezed or worn out

Basically, turn off your hvac completely, see if it makes the noise. If no, turn the AC on to full blast, blower fan on, and check if it starts making the noise. If yes, then there is your issue, but honestly thats what it sounds like since the AC compressor turns on and off all the time when its in use, its not designed to run 24/7

They most likely will not replace this part, they will opt for replacing the whole AC compressor, but if its under your dime, fight for just that piece as its obviously much cheaper.

hrmmm ... sort of sounds like it could be wastegate rattle.... *google that issue*
but im leaning towards no.

take it to the dealer

I don't think so, would the wastegate open/close at idle like that? shurg?:confused:

Watched some stuff on youtube, doesn't sound like the wastegate rattle, but shurg! who knows, do ac test first, i still think its the AC clutch pulley being noisy

^ thanks! I'll do some more google'ing and reading on the AC system. I like to at least pretend I know what I am talking about when I talk to the SA's.

Have appointment tonight after work.

... i see you googled the issue after ;) . its quite a common problem on the car. and I agree Im leaning towards no of it being the cause.

but OP should just stop having us playing internet guessing games and take it to the dealer before warranty expires.

Did you atleast check the oil level ? e90s dont have dipsticks right? Does the computer tell you the oil level or just life?

Probably not the issue, start with the basics, low oil level can cause lifter noise, as well as many other things like wrong oil, broken down oil, etc..
Plus if you follow BMWs oil change interval, then there is a higher chance it's low on oil if you're towards the end of that interval.

It's not an oil LEVEL issue according to the car. IDK what oil they used, but since it's the dealership I expect that it's the proper kind. The car was supposedly just serviced and brought to CPO (Certified Pre-Owned) status. That's part of what disappoints me. Paid EXTRA for this because I got it from a dealer it was supposed to be in perfect condition. (to their credit, I have new tires, pads and rotors and all the other "check" systems in the car show 10K+ kms until service)

If you bought it CPO they should be dealing with these issues, let them sweat it.

I agree...I would head to downtown BMW, and like I originally stated tell them the car is making noises, and you don't feel safe driving it.

They have an obligation to check and correct the issue.

I would be livid with them if they said no. But Downtown BMW has always been friendly when I go there. I can't imagine them turning you away.