Yamaha stalls, sputters and backfires
 

After last year's annual service on my 2010 Yamaha my golf cart would stall if I let off the gas and suddenly stepped back on it again. I took it back and they said it was a clogged fuel filter. That wasn't it because it does the same thing when it is cold, or when I have been coasting or stopped for a second. You step on the gas and nothing. You pump the gas pedal and it backfires. After a run and you park it in the garage you get a strong smell of exhaust and the exhaust pipe has pitch black soot in it.

Any ideas of what the problem could be?
Thanks!

How fast does it go and what was adjusted to allow the extra speed?
It Could be governor out of adjustment or also carb could need adjustment ,removal and cleaning cleaning.
If the annual service was recently done why did you need another fuel filter?
There is a sequence of adjustments and observations that should be made during a service to accomplish a good running cart

How fast does it go and what was adjusted to allow the extra speed?
It Could be governor out of adjustment or also carb could need adjustment ,removal and cleaning cleaning.
If the annual service was recently done why did you need another fuel filter?
There is a sequence of adjustments and observations that should be made during a service to accomplish a good running cart