snaps2k

Today as I parked and turned the ignition key to 'off' the car continued to run irregularly with a grinding noise and light white smoke from underneath the throttle cable/headers area. Turning the key back to 'on' stopped the grinding and the car would idle and rev normally with no issue, but any attempt to turn the car off like normal would result in more of the grinding and burning/ozone smell.

After purposely stalling the engine to get it to stop running, the ignition button now clicks but the car no longer starts. All electronics still seem to work in the cabin and dash lights, and there is no CEL on the dash.

From what I figure, I experienced Run-on or dieseling (http://mgaguru.com/mgtech/engine/ro101.htm), but I'm not sure why that would have affected the starter motor. The last maintenance I performed was cleaning the PCV valve, IACV and performing a map whack, but that was over a month ago and the car has been driven daily with no issues until now. This did happen on a new tank of Arco 91 premium gas, so perhaps they had quality issues with that batch of gas?

I've ordered a new starter motor for now, but is there anything else it could possibly be?