syswei

This is my very first MB (we also have 2 Lexus SUVs, will be selling one)....so possibly this is normal but please tell me:

After I park and exit the vehicle, sometimes I've noticed a loudish hissing sound, like air being let out from the front end...I presume the suspension.

Then, even 30 minutes after the car has been sitting, if I return to the car (without the keyless-go key fob) and simply touch the door handle, I get more air release / hissing. This last time when I tried it, touching the front passenger handle (at the sensor), I paid attention and noticed the front end actually lowering as the air was released.

So, is this normal, or is it another reason to go in for warranty repair (the other reason is that locking the car from the outside, by touching the door handle sensor, usually doesn't work)?

BTW the car is an 08 S550V4, P3, Distronic, prem. leather, side power shades, heated wood steering wheel.

Saverino

That is 100% normal. Like you said, its just the air suspension. Nothing to worry about, at all.

cgjungdds

yeah mine does same thing -- actually think it is kinda cool sounding
oh yeah i am having occasional problems with the touchy keyless go thingy on the handles -- let me know what they tell u about that

steveb9771

With keyless go, you can lock the car by touching the outside of the door handle anywhere. You don't have to touch the square.
I do not believe the hiss you are hearing is normal. I have a CL550 and there is absolutely no hiss sound. It has the air suspension system.

AustinGuy

The hissing is absolutely A1 normal.

I kind'a like it actually . Everytime I hover around the car or at night.... when I kiss her goodnight, I like to hear her hiss in my ears.

Quite cool actually.

WSH

The weird noises seem to be an Airmatic phenom....never heard such stuff on ABC-equipped S/CLs....

dadesidon

It's an Airmatic thing. Ours does the same thing. Personally, I think it is very cool.

ahmadkshuja

+1

AustinGuy

It's like she's letting you know that she's knows you are there.....

Ferri

You actually have the ABC, which does not make the hissing sound. Syswei, your car is going on rest mode (lowers) and usually upon start it goes back up to normal ride height, at least so did the last Airmatic I experienced (220). Whereas hissing should be that loud, I am not sure.

ahmadkshuja

+1

cgjungdds

i'm with you all -- like she is saying goodnight i named her Maggie and she talks to me sometime

syswei

Thanks for the replies, everyone. I guess I can understand the car returning to "rest mode". But what I don't understand is why, if I return to the parked car 30 minutes later and touch a door handle (I think without the keyless go key fob, but maybe that doesn't matter) I get more hissing and the front end visibly lowering. If the car wants to be in rest mode, why not get all the air release over with soon after parking? Do other people's cars also do the "late" air release I'm describing, or is there possibly something wrong with my car?

dieseldoc

Very normal, My GL does it.

Beno

Absolutely same here, I don't think anything is wrong

Sorry for OT, but I borrow little this thread. I wanna save Mercedes Engineers time (and mine aswell), so what might be wrong with my drivers seat? I have drive-dynamic seats, and when I set 'support-mode' 1 or 2 (0 off) it usually comes instantly off. Sometimes I am able to use it minute or two, but after cornering it comes off. Recently left air bladder was changed because it was broken, at the time it worked as it should - the left side just didn't fill up. The Car doesn't give any error message, and my dealer says it could take some time to find out whats wrong

Diesel Benz

What is your car's serial number? A range of cars may have a faulty valve electronics. But I believe this would be more like valves operating on their own or not operating at all (sometimes). This sounds more like the dynamic mode is exited for some reason.

I think I've seen a similar complaint before, might be difficult to find but a search could bring it.

In any case a good idea to ask from this forum, someone may know it from experience and there are very good dealer mechanics attending, much better than at your garage, if they are anything close to average.