St Elmo's Fire
 

I replaced the coil wire in the SEL the other day, and tonight, on a test run, I opened the hood (it was dark out) and my ignition coil wire was ablaze with blue electrical glowing down it's entire length....My local parts place lists a spark plug wire set for $299 :(

What causes this in a new coil wire? or any coil wire for that matter. I also see some arcing between the coil bracket and the body of the car.

I dont know about the fire but I paid $175 for wires at the dealer so maybe they have them cheaper...

PanzerSD, apparently the coil is bad. Try replacing the coil (either swap a known good coil or buy a new one) before going to the expense of replacing all the ignition wires.

the new wire I had measured 6.5k resistance....cleaned up and re installed the old wire. even with it's bleeding energy is still better than that 6.5k wire.

that happened to me when I armoralled my grille.Got silicone over my wires

They bled energy from having silicone on the wires?

Mercedes have solid core wires. The coil wire should read 0 ohms.

Paul

I thought MB wires were resistive and that's why we need the non resistive spark plugs? I don't know, just repeating what I've read many places. I would like to know for sure.

the lengths of wire themselves, are solid core, o ohm wires.
low resistance, high RFI The ends (the can be removed) are resistor ends, at 5K I believe. which makes the assembly less active in transmitting RFI (buzz in your speakers)
testing ohms should be done as an assembly (2 ends and a wire) but you can test in pieces if you REALLY want to be sure..