My 1984 280SE (Euro) 240k km., was misfiring occasionally at higher revs.
Blue sparks on the distributor cap, (corroded coil terminal, probably the
original cap!) 2 (!) plug electrodes almost eaten away, so changed all HT
leads, distributor cap, rotor arm, oh and new plugs ! Now pulls strongly
from 2000 to over 6000 rpm, but idles like a 5-cylinder. No oil in the
water, no water in the oil, spraying diesel start around can't find any
Are we talking head gasket between cylinders, or leaking hoses or what ? Any