Vacuum closers for doors & trunk - PeachParts Mercedes-Benz Forum

JP1 · #1 08-04-2003, 04:20 PM

Following the owners manual for my s320 1998 i pull the fuse for the closing assist mechanism, wait 30 seconds put it back. My trunk and all four doors work via the assist. However, in a few days the trunk stops working and then the drivers side doors all together. The passenger side doors still work via the assist. I dont know whether its a problem with the master vacuum pump in the trunk or is there another one in each door, but even so why would the trunk quit working also? The handle retracting on the trunk continues to work the trunk just doenst draw closed. Any help would be appreciated thanks JP1

#2 08-04-2003, 05:02 PM

Do a search using closure assist. The same thing has just happened to me. I believe the pump will need to be replaced. My understanding is that there are valves in the pump that regulate the different doors and the trunk. I pulled #9 fuse and the assist works again. Lets see for how long.

JP1 · #3 08-05-2003, 08:37 PM

Thanks HPF after replacing the fuse 9 again mine lasted a few days but now is doing the same thing. I guess i wll have to tear into the trunk lining and get a part number then try to find it on ebay like one of the other guys instad of eating the full price for a new one. I sure wish there was a place to order parts at a reasonable price. The other thing thats bothersome in reading all those sessions on clsoure assist is that they seem to move back and forth on the location of this pump in the trunk, and these blak snaps that you have to take off the lining once you pry them off some of them break as they are plastic so we will have to order new platsic snaps to put the lining back in place. Thrid on this s320 the pump isnt on the drivers side cause i got that lining out it must be against the back seat, either way 500.00 for the part hurts any and all suggestions welcome thanks

#4 08-05-2003, 09:52 PM

Hi JP1,

In regards to parts: if you can not find the pump on EBAY I would suggest you use the net to find a MB dealer maybe out of state of where you are.

I have found that here in California the dealers mark up the prices about 25% over what I can get from another dealer in Illinois. I just ordered a bunch of items that I needed and saved myself close to $250 as compared to if I had bought the same items from my local dealer. Also they did not charge me tax or shipping! Shop around!

Good luck with your project. Let me know how it works out.
Tom

JP1 · #5 08-06-2003, 10:17 PM

Great ideas will research and let you know how it goes thanks

Peter Guenther · #6 08-20-2003, 08:23 PM

There are two pumps one is for the closing assist (pulls doors and trunk lid in) those pumps fail regularly. This pump is located over the rear wheel next to the gas tank, remove both liners to get easy access(wheel well & gas tank/package tray)
The other pump controls , the trunk handle, lumbar, headrests if you dont have electric rear seats, central locking, and provides vacum for the HVAC. It is located under the rear (passenger) seat. This one does not fail as often. There was a bulletin about 95 cars having a bad hose inside the closing pump and a hose was available from MB, but that would indicate all doors would not pull in.
I am a little leery about buying one one bay, you could get one as god as yours. I purchased a new one at MB and it failed 3 years later, they did replace it, since they installed it.
George Barrett rebuilds them and gives a warranty, he advertises in the STAR

GermanStar · #7 08-20-2003, 10:30 PM

These pumps are readily available new on the aftermarket for about half of what the dealers get...

Ron
http://germanstar.net

h_shek · #8 08-21-2003, 07:28 AM

I had the same problem with the pump but luckily I seem to have fixed it.

The pump fail because it tries to "suck" the door and after trying for some time, it quit sucking and time-out the pump. The #9 fuse trick merely reset it until it quits again.

What I did was that I disable the trunk pull-down entirely by removing the hose that does the pull down. The trunk have to be shut harder but that's fine for me as I can adjust the catch on both side to shut with as little effort as possible.

It seems with one of the hose removed, (can't remeber which one but I am sure you can try) all 4 doors seems to have the close-assist function working very well. I have not been resetting my pump for 3 months.

I also figured that with the plastic cushion housing the pump removed, the pump would work fine as it breath much better. This will be my next bet if the pump fail on me.

I am happy that I fixed this little one so far as the pump isn't really broken down. Just a bit inefficient and the computer time-out the bugger!

Give it a try before forking our $$$

JP1 · #9 08-21-2003, 11:17 PM

Good suggestions i will try it this weekend before i buy a new pump. I have been having problems getting the liner in the trunk on the passsenger side(gass tank side) of my s320 off. I keep popping the black plastic pieces that hold the lining off carefully but i have already had two break so i am trying to find new ones for that also. and be a little more careful. I am going to go at it hevay this weekend and if this doesnt owrk then i will buy the pump thanks all for the suggestions. Will post how it goes JP1

tivoliman · #10 12-29-2005, 11:41 AM

I was reading your post - which ended that you were going to try this weekend.

Did you buy a new pump? Did removing the hose make a difference?

What is your general comment regaring fixing the vacuum assist doors?