I have a 1994 S500 that owns me (no, that is NOT a typographical error!!) and She has developed a problem. The doors on this car have a vacum assist closure, or at least that's what I call it Anyhow, the problem is with the drivers door....it no longer closes like the other 3 do. When I close it, I have to close without the assist. At the same time this happened another little problem arose. Now, when I shift into reverse, the trunk opens!! I know Mercedes has many innovative options on their cars, but I don't think that is one of them!!LOL Anyone have any ideas when my driver door and trunk lid decided to get minds of their own? Also, just one more question, what good does disconnecting the battery for a short period do? I've read a few posts here where that 'cures' some minor ills, like what? I'd go back and try to find those posts, but I'm too damn lazy!! Seriously, any help would be very much appreicated. THANKS!!!!

 

There is a vacuum assist pump located in the trunk area, left side when looking into the trunk, behind the back of the trunk covering. Behind the covering, and wedged in next to the gas tank is this vacuum pump for the doors, trunk, etc. The pump does go bad, but usually it is in need of tightening bolts and screws on the pump body, and ensuring vacuum lines are not clogged and that all of the multiples of vacuum lines going to the doors, etc are tight. It is a pain to remove and clean and tighten and re-install, but worth it. Disconnecting the battery is the same as removing this pump's fuse for a few minutes and then reconnecting. This usually clears any memory of a door not closing three or four times in a row and then the pump controller locks out any more vacuum to that door(s). I removed and cleaned and tightenedthings on my pump and reinstalled in about two hours. No problems ever since. Worth it to try the clean and fix first, rather than replace this expensive thing. Trunk coming open in reverse is odd; usually means it was not closing right to start with, not because it was placed into a movement gear. www.alldata.com should show the maintenance steps. I found out how to do it via a webpage someone created just for this maintenance procedure. If I find that link at home later today, I will send to you.

 

Thanks for such a prompt reply wmercer!! Now that I know where that pump is, I'm going to take your advice, pull it, clean it and tighten it. However, I'll wait until, hopefully, you can find that link. If you can't find it, your instructions are quite clear and I shouldn't have any problems. Thank you very much for your reply AND advice. It is much appreicated!! Just one more thing, which is more of a personal observation then anything else. I never thought I'd find a car that I love as much as this old girl. She's big, expensive to repair, and eats gas like nothing else I've ever had, but now I know what they mean when they say: 'You don't get into a Mercedes...a Mercedes gets into you!!' Damn these cars ARE addictive!!! And now I can see the importance of a forum like this. Without you guys, and gals, I'd be in the poor house by now!!! Thanks to all of you for all your help....you have saved my sanity....and bank account!! Granted, I don't post often, but I'm here at least twice a day and have learned so much from all of you. Again...THANKS!!!!!!

 

this should get you going again...

http://v12uberalles.com/Closing_Assist_Pump.htm

or, at below link, scroll down until you find the pump information..
http://www.benzworld.org/forums/w140...ge-base-3.html

last resort -
Ebay Item number: 320123686731

 

Wmercer, people may say alot of things about you, but they sure CANNOT say you're slow!!! Damn that was quick!!! Thank you so very much for the reply and the link. I'm going to print it and start the procedure tomorrow. I'll let you know how it goes. It may take me awhile since I'm unfamiliar with the process, but that link you provided I should have no problem. Again, thank you very much for your help!!!

 

Ok.
Wonder what is it that people are saying about me.
Good Luck.

 

Good going there Puck...'open mouth...insert foot!!!'LOL Wmercer, I didn't mean anyhting by that, except for the fact that you got back to me really fast!! Actually, all I have ever heard about you was how great you are with Mercedes, how knowledgeable you are, how friendly and helpful you are. And that you are just an 'all around' good person!! Also, that you are well liked in your community and have been nominated for best 'poster' here on the forums, which you in your humble way, gracefully declined that honor. (Puck to self; WHEW, I sure hope wmercer falls for that line of crap because I sure don't want to make any enemies on this forum!!)LOL!!! Seriously, I didn't mean any offense by that rather stupid remark. But then again, if you knew me, you'd realize that I have a tendency to make ALOT of stupid remarks. Have a great day!!!!!
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Got it. All good. Thanks.
Prior to doingall of this, remove the fuse to the pump (could be even two fuses) or the battery cables (then you will need to reset radio code and windows, memory, etc). When you get this pump out and the cover to the pump off, concentrate the thoughts first on carefully and easily tightening every screw or bolt you can see. Then, look at the vacuum lines going into and out of the pump itself, carefully, at one end at a time, blow by mouth or very low pressure air, any residue out of the lines and pump cover, the years of carbon, dirt, etc, accumulated. Reassemble. while still not back into it's "home" place wedge next to the gas tank, test and check it’s function.
Hope it works for you

 

Wmercer, sorry it took so long to get back to ya, but I just wanted to let you know that your suggestion cured my door problem AND my trunklid problem. Admitingly, it gave me a fit when I first started because I think I was in too much of a hurry. So I calmed down and now the Little Lady (if you can call a '94 S500 little!!!) is working just great again. Thank-you wmercer for your time and very valuable assistance. Trust me, it was very much appreicated. I owe ya one!!!!