In message , at
12:33:56 on Sat, 18 Apr 2015, BazzaSoft
remarked:
Many years ago my father-in-law experienced a similar problem with his Mercedes 190 estate which roared away and could only be stopped by
switching off the ignition. It did this more than once and it was apparently caused by a carburetter malfunction. I suspect the BorisBus
doesn't have carburetters but the Mercedes in which Princess Diana was killed probably did.

I very much doubt the Mercedes you mention was anything other than fuel
injection.

30 yrs ago I borrowed a colleague's hot hatch for the weekend (maybe a
VW Golf) and a couple of times it "ran away" because the accelerator
cable got caught on something, probably due to a half-arsed conversion
to RHD.
--
Roland Perry