Honda 2012 TRX420TM Owner's Manual page 198

If Your Engine Quits or Won't Start
SYMPTOM: Engine starts, but runs poorly.
POSSIBLE CAUSE
high coolant
temperature
runs erratically,
misfires
blubbers (rich fuel
mixture)
sooty exhaust (rich
fuel mixture)
detonates or pings
under load
afterfires (backfires)
pre-ignition (runs on
after ignition
switched OFF)
SYMPTOM: Engine starts, but runs poorly or dies when hot.
POSSIBLE CAUSE
poor or inadequate
fuel flow due to
clogged fuel filter
190 Taking Care of the Unexpected
WHAT TO DO
Check the high coolant temperature
indicator. Refer to If the High
Coolant T emperature Indicator
Lights, page 195 .
See your dealer.
See your dealer.
See your dealer.
If applicable, switch to the
recommended octane gasoline
(page 102 ) or change your brand of
gasoline. If the problem persists, see
your dealer.
See your dealer.
See your dealer.
WHAT TO DO
See your dealer.
(ensure clean fuel supply)