I'm used to muscle cars and Honda's, not done a lot of work on Mercedes. Here's the problem, and I think it's the #6 coil pack but I just wanted to see what some Mercedes people thought or whom may have experienced the same problem would say...

Idles rough and dies when you come to a stop. Starts back up and will die by itself if you don't give it any throttle. Checked codes a while back and Cylinder #1 misfire is the only one that popped up. Checked the plugs today and sure enough, cylinder #1 had little to no use out of it. The other 5 had very healthy looking coloration.

I noticed (Bear with me, like I said, I haven't done much Mercedes work) that #1 cyl is ran by #6 coil pack, #5 cyl is ran by #2 coil pack, and #3 cyl is ran by #4 coil pack. I checked all the wiring connections every where. Checked vacuum lines, checked everything. The only thing I can think is that the #6 coil pack isn't putting spark out on a consistant basis (#1 plug did have some use, but no where near normal) to the #1 cyl.

Has anybody else experienced this before? I'm working on this car for a friend and would not like to have her spend the 85$ for a new coil pack if somebody else has experienced this before and it's something else. Just from what I've seen, it can only be the #6 coil pack messing up and not putting spark through to the #1 cyl.

Any input would be awesome as I'm trying to get her back on the road safely within a reasonable time frame, so huge thanks to anybody that can offer some assistance.

And if you're wondering, yes, I did use the search function and didn't find anything specifically like this. A lot of threads about removing the spark plugs, but none about this specific issue. I may be new to Mercedes, but definitely not new to forums

Again, thank you for any and all input. It's hugely appreciated.

-Chad

 

The easiest way to check whether the bobbin is the culprit is to switch it for another cylinder bobbin and see if the #1 cylinder works well and the other one misfires.

 

That's exactly what I was going to say. It sounds like a problem I was having, and after replacing the coil pack it works fine. By switching it, if it's bad, you'll get an error code for that cylinder. Then you'll know.