mel

I have a 300TE-24 from 1991. When I bought it for about 4 months ago there was a slight problem before I got it. When I testdrove it it stalled and stopped after about 10 minutes of driving. I managed to take it back to the dealer by running it at idle, because each time I touched the accelerator the engine died. I had a mechanic to drive it again because we suspected that there was water in the system after they had washed the engine. It run ok and I bought it. After running appx. 2000 km it again died for me. Exact the same behaviour ie. after 10 minutes of driving it stopped. After letting the car cool down it starts and runs without any misfiring. I let the car be for one week and took it out for a spin and voila, 10 minutes it stops.

I think I have traced the problem down to the petrol pump relay. ( Don't know what you guys call it. ) The problem is that I have the CD's with schematics but I don't know if things looks the same for the 24 valve model as for the regular 300. I know that it should be housed behind the battery but don't know what gizmo is the right relay.

Does any of you know anything about this problem? I've been informed that this is a known problem for the 300-series.

dlafever

Mel,

What you are looking for is a little green ice cube with a 30A fuse in it. There may be more than one since these relays are also used for the auxiliary fan(s). The part number on the top is 001 542 96 19.

Cheers,

-D

mel

Thanks for your rapid reply!

Are you sure that this is applicable for the 24-valve? I have only got the schematics for 12-valve 300's.

dlafever

Glad to help if I can Mel! After all where would we be without Glog?

When I looked it up it appeared to apply to everything from 1989 - 1995 that was not an S-Class car, so I think it should be the one. To get a visual on it, you can go to http://www.buymbparts.com and type the part number (001 542 96 19) in the box on the left hand side of the page. Click on the picture to zoom in. I would post the image, but for some reason I can only post 1k of image attachments! Click on the picture to zoom in.

Essentially it is supposed to fit the following (partial list):

124.003
124.004
124.007
124.008
124.019
124.020
124.022
124.026
124.028
124.029
124.030
124.032
124.034
124.036
124.040
124.042
124.051
124.052
124.060
124.062
124.066
124.079
124.080
124.081
124.082
124.083
124.088
124.090
124.091
124.092
124.104
124.105
124.106
124.107
124.120
124.126
124.128
124.129
124.131
124.131
124.138
124.180
124.185
124.186
124.188
124.290
|
etc.

mel

I went to my local MB store today and now I am really confused. When I talked to the mechanic he said that there is no actual relay on my model but instead it has a 'MAS unit' ( ? ). He didn't think that the problem was related to the fuel, it was his opinion that I should check the ignition instead.

The fact that I haven't been under the hood yet does not help me at all, and I will dig deeper into it during this weekend. I haven't got any garage on my own and up here in the cold north there is no fun at all to stand on the outside probing for error

Was it your own experience that it might be a faulty relay?

dlafever

Hey Mel,

Yes, it was my own, although with a '84 380SE. They had a much larger fuel pump relay and I fixed it by resoldering the PCB.

-D

dlafever

Mel,

Just skimming through eBay today and found this:

http://cgi.ebay.com/ebaymotors/ws/eB...category=42612

Although it does not seem to apply to your car it does seem to answer your question, looks like the relay is indeed part of the MAS unit! Sorry for the misleading information earlier

Good luck!

-Dennis

mel

I was under the hood yesterday and found the MAS unit. I also found it in the CD-dockumentation I have. I will try to borrow a unit from the dealer to see if this is the problem. I also discovered that there i two fulepumps in my car, so it might be that one is faulty.

The struggle continues. Thanks for your help!