brt3

My car's about a month old and has made a very odd noise on three different occasions. It sounds as though it's coming from the middle of the car. My wife thought it was coming from the dash, but to me it sounded as though it was in the middle or rear of the car.

It sounds like an electronic sounding beep with a squealing variation in pitch at the end. It lasts for no more than 2 seconds max. It always scares the hell out of me as it's loud enough for me to think it's my radar detector going off.

On two occasions I was driving quickly around a right-hander, pretty high G-loading right at 80 mph. This made me think the noise was somehow related to hard cornering. I'm assuming the air suspension has a compressor, and thought that somehow this was getting worked harder in cornering situations.

Any ideas???

MBE55AMG

Supercharger squeal, maybe?

onesixeight

I don't think it's the airmatic compressor...the compressor is more of a low, "brrrrr" kind of noise. I rarely hear the airmatic compressor once the car is moving.

I'm thinking the the supercharge squeek too...sometimes that squeek can be high pitched, but I'm not sure if I would call it an "electronic" sounding beep.

brt3

Thanks for the input. Supercharger squeal is the first thing I thought of, but this really sounded like it was coming from the middle of the car. Besides, it was quite loud -- as I mentioned, I thought it was my radar detector going off. Definitely a "squeal" towards the end -- it was a steady pitch at first, but the pitch changed towards the end -- but high-pitched enough to sound like an electronic beep or warning at first.

How loud is the supercharger squeal? I thought I heard it when I first picked up the car, but this initial sound was much quieter and would have been drowned out had I been listening to the radio. The noise I'm hearing now is very loud and quite annoying. How is the supercharger squeal related to throttle position? The last time I heard the noise I was motoring along very quickly, but was either at a steady-state throttle position or light acceleration.

If this is one manifestation of supercharging chalk up another customer for the 6.3 normally aspirated engine.

Seriously, though -- I love this car despite its' flaws. Just hit 1,000 miles, which allows my Puritanical conscience to use full-throttle without guilt. Filled her up with gas at Costco early this morning and, upon leaving was presented with a nice, straight empty street. ESP switched "off", light turns green, and with only about 2/3 throttle the rears spun for about 20 feet. The expression "sh*t-eating grin" applies here...

AMGe55

My car had made the same noise a couple times, usually right after I started it and was backing up. It is not the supercharger chirp because I had that too. This sounds like letting the air out of a pinched balloon. It is a short squeal like sound that lasts a second or two. It sounds like it is coming from the rear seat area-hard to pinpoint exactly. Not sure what it is-it only happened when I was going slow after starting the car. I never had any faults show up so I ignored it.

brt3

This sounds like exactly the same noise I'm hearing -- same frequency (I think), same location, same duration. Has anyone else heard of this? Wonder if the air compressor occasionally builds up too much gas, and has to (loudly) fart it out?

mrankovic

This seems very strange. I can't help you with what it IS, but I can help you for sure and confirm the other post that it is NOT the supercharger chirp. That is a very distinctive chirp that comes from the engine bay, and it only happens when you floor the car on take off and is caused by the belt somehow slipping on the pulley (and that's what it sounds like) and lasts like 0.25 sec (or thereabouts).

I think a call to the service manager at your dealer is in order. Since there is another post on this board about it now, this means the dealer should have heard about it in the past.

BoBcanada

I had it, search for noise and find a thead under my nick and if it sound familiar go to the dealer.

pas

I have a 2005 E55 and my car has begun making the same noise you describe. The noise started after I had taken the car apart. I removed the rear seat and headrests and also the c-pillar cover and items behind it. A palm frond fell on my car and made a nice dent and I was trying to find a way for the ding guy to get to the dent. Anyway inside there I removed a piece of the car the is part radio antenna, part rear defroster connection and seemingly somehow related to the SRS system I also disconnected the wiring to the seat belt. After I had put everything back together, I heard the noise a couple of days later and it appears about once a week. My SRS light is on and I haven't had a chance to take it in to have it reset. I also removed the hardware associated with the airmatic system in the trunk on the drivers side behind the nav dvd player. I'm guessing the noise is coming from that electrical piece that has multiple functions and I had assumed having the SRS fault cleared at the dealer would solve but I really don't know what the cause is. Sorry I couldn't offer more insight. After I make it to the dealer I will follow up with any changes. To me it doesn't sound like air from the airmatic system it sounds like an electronic noise. Also if you have a dent in the c-pillar don't bother taking the interior apart unless the dent is very close to the rear door, the only access is through the trunk.

brt3

Thanks for the input, guys. Pas, in my case the noise starts out sounding somewhat electronic, but then changes to the "pinched balloon" sound towards the end. Will speak to my dealer about it, but I'm not going to give them the car until I've done more research. I'm in Marin County, CA, and the local dealer is not the greatest. Considering I didn't buy the car from them I'm expecting the same second-class citizen routine I got with my G500.

Mrankovic, I agree -- I'm certain this is NOT supercharger noise. I have heard the noise people describe as SC squeal, but only very faintly. I think the owners with this problem have far more mileage on their cars, and that this noise increases with mileage (to a point) and becomes much more noticeable than on a new car...

mrankovic

Yeah that is true... So unfortunately just as you get the squeal sorted, you'll probably be the recipient of a chirp!

AMGe55

My car only had about 5K miles on it the first time I heard the squeal sound. I just sold the car a week ago with 13K miles on it.

HawaiiC32AMG

I am not sure if that is the sound u talking about but I notice it will come on once in a while from the suspension/ airmatic when it is I think either the car running or not. Either the car is lowering itself or getting higher / original height at low speed. Is that the one u guys talking about? It only comes on once in a while...more like a do..ill...do.ill...sound. Sometimes it also happen when I used the remote unlock the car and open the door, it will come out....strange.

brt3

Hawaii -- that's a different sound from what I'm experiencing. This is one thing that scares me about the new BMW M5 (I have one on order); these cars are getting so many gadgets that buyers end up becoming beta testers. The more gadgets, the more there is to go wrong...

^E55^

yes. my e55 also noisy, the noise from engin bay become bigger that before.........so the e55 it's very noisy..................

ApproachingZero

????

psk145

mine does the same intermittent noise, but only after I spray my car down when Im washing it. If the car has been driven, it will do the electronic beep/squeel thing. It continues until Im done washing and start the car up again. I asked the dealer about it, but I got the "could not replicate" line.

its definitely not the same noise as the airmatic pumping up

sti05ak

when i hit it in 1st and let off i hear the supercharger squeel

jmb614

Bumping the dead. All apologies but I am having the same issue. Very loud high pitched sound that changes pitch with a change in throttle. Once the engine heats up it usually goes away. I thought I had found the issue by spraying some TB cleaner around the passenger side surge tank flange near the firewall. Just a small shot, the idle changed and the sound went away.

I've replaced the surge tank gaskets twice now, following proper torque procudures and still this damn sound persists. Anyone have any ideas? I've also tried some anaerobic permatex on the gasket, still no luck.

izzyz28

I've had this happen a few times. It sounds like an electronic, high-pitched sound and it comes from the left(driver side) C-pillar area. For a while I heard it a few times in a couple of weeks, and then it mysteriously stopped. Usually when I was in my driveway, but it happened while driving too. I have no idea what it was, but it was unsettling.

HawaiiC32AMG

It's a known issue from the Supercharge....MB said no fix and is normal...I sold mine already.