lets see just how much you guys know about 140s
 

Here is a crazy story. I parked my 1993 400SEL and because I was putting a laptop in the trunk, I also closed it by turning trunk lock clockwise all the way.

I then opened car via remote on drivers door ( no key used ) and checked to see if trunk was double locked. To my dismay opening the car from drivers door via remote, unlocked the trunk also, in spite of the fact that I thought I properly locked it .

Thats the easy part. After a few hours I came back to car, opened trunk via trunk remote, and put laptop in passenger seat, using passenger door. Then I started car from passenger side and walked around to get in and drive.

Now here is the eeire part. I heard a moaning like I was low on power steering fluid and popped hood to see that I was down a little but not enough to make that sound in the past. I started driving and the sound was similar to PS moaning but happened only when I applied brakes.

Eerie sound like nothing I ever heard before in a car, almost like a moan or like an alarm or horn of some type but much lower than either. I remembered the car has an alarm and if I confuse it , it will refuse to start, horns will blare etc.

So I thought the only thing I could try was to lock and unlock the trunk using the key instead of the remote. I locked it with the key from trunk lock, and saw the light go orange , and then go green when I unlocked it with key again all the time using trunk access.

I did this 2 times in both clockwise and counter clockwise direction, and when it was in open position ( after flashing green) I went to drivers door and started her up .

Moan, groan, humming alarm horn whatever it was went away.

Knock yourselves out :)

Old cars do weird things sometimes...nuff said.

It's a Gasoline W140
 

Umpity,Zump more electro-wizzardry to pull a "Lucas" on you ,Than the Diesel.
'Wunnerful Chassis RIDE,like no other 'Benz...
'Frought with Uber expensive idiosyncrasy (s),that are difficult to diagnose.

What I know about 140s...hmm...RUN!!! :D:D

If it is any help, I have noticed that the hydraulics in the transmission in my SD whines a bit at a stop and/or slowing. I thought it was the PS for a long time but after a flush it persisted...narrowed the sound down to the transmission. Usually much more noticeable when cold, but it sounds EXACTLY like PS pump whine. Just a thought.