See picture below:
Has in inductive pickup of some sort on ignition lead #1. Other car I've seen (a 1974 450SEL) doesn't have this. Curious to know what it is and if I can ditch it.
(http://ianmav.customer.netspace.net.au/mercedes_b/450se-_22.jpg)
You can ditch it. It's purely for hooking up to an appropriate Bosch or similar d-jet diagnostic tester.
Mine's still in place though. But it's useless without that inductive coil on the lead. I think the only way to get that coil on or off is to unscrew one end of the ignition wire so the coil can slide on or off. That's what I did when I replaced the Beru leads with Bosch.
EDIT: I remembered why I left mine on. It was connected to the control module as well plus a TDC sensor and I just haven't been bothered getting round to removing it all.
From an old thread re ignition wire diagnosis cable @ $433US back in 2005 -
(http://images.andale.com/f2/104/120/20810658/1121909228002_102c_1.JPG)
Thanks. An uncluttered engine is next to godliness...