MZ/MuZ Riders

my 1000st ran on to one cylinder recently and despite my replacing the plug and the pencil coil it still refuses to run on the suspect cylinder. Any suggestions?
George

You may have already done some of this, but assuming you have'nt, I'd start with back tracking and checking the wiring connectors to the ECU.
Then remove the coil from the plug (leave the coil connected to the wiring harness, as well as leave the sparkplug in the head) and stick another sparkplug in the coil, ground the sparkplug somewhere on the engine (don't hold the coil....I believe theres exposed metal on the sides?) Fire up the bike and see if it's sparking.
If it is I would assume the fuel injector is not working/getting fuel? The manual works from the small to big of: connections, shorts, open circuits, component failure, and the last resort being to contact MZ...which probably means the ECU is afoul. That's assuming the diagnostic tool is being used. Everything is a just guessing game otherwise....have you disconnected the battery for a few minutes and reconnected. On some vehicles that is required to reset the computer. Again, just another guess. That's all I've got. Good luck!

LWS66
Many thanks for a prompt reply. I have tried the spark test, and no spark appeared. I am now tracking back to the ECU. I think that the injector is operating as unburnt fuel from the dead cylinder was causing the catylist to incandese and raise the exhaust to dull red.
George Waite

George,

Do you have a volt/ohm meter? With it set to any of the ohm various settings you could check the wiring harness "terminal to terminal" for any open circuits: broken wire (doubtful) or broken solder/crimp (very possible)...my horn button stopped working awhile back, turned out to be a broken solder joint at the switch.....and the way these things vibrate it's not out of the question. Checking the wiring this way would for certain eliminate or identify any issues with the wiring....use the methodical and logical way of diagnosis, this according to my electrical engineer father in-law, seems reasonable enough to me!!

"one issue is that the coil can get corroded if it gets wet seal it with some epoxy."

this was in a past post on the 1000s
check to see if coil is getting proper ground
ar dave

thanks for the advice folks, faulty coil with intermittent fault responsible .
regards
george waite