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17-30 APPENDIX
Troubleshooting Guide
NOTE
○
Refer to the Fuel System chapter for most
of DFI trouble shooting guide.
○
This is not an exhaustive list, giving every
possible cause for each problem listed. It
is meant simply as a rough guide to assist
the troubleshooting for some of the more
common difficulties.
Engine Doesn’t Start, Starting
Difficulty:
Starter motor not rotating:
Starter lockout switch or neutral switch trou-
ble
Starter motor trouble
Battery voltage low
Starter relay not contacting or operating
Starter button not contacting
Wiring open or shorted
Ignition switch trouble
Engine stop switch trouble
Fuse blown
Starter motor rotating but engine doesn’t
turn over:
Immobilizer system trouble
Starter clutch trouble
Vehicle-down sensor (DFI) coming off
Engine won’t turn over:
Valve seizure
Valve lifter seizure
Cylinder, piston seizure
Crankshaft seizure
Connecting rod small end seizure
Connecting rod big end seizure
Transmission gear or bearing seizure
Camshaft seizure
Starter idle gear seizure
No fuel flow:
No fuel in tank
Fuel pump trouble
Fuel tank air vent obstructed
Fuel filter clogged
Fuel line clogged
No spark; spark weak:
Vehicle-down sensor (DFI) coming off
Ignition switch not ON
Engine stop switch turned OFF
Clutch lever not pulled in or gear not in neu-
tral
Battery voltage low
Immobilizer system trouble
Spark plug dirty, broken, or gap malad-
justed
Stick coil shorted or not in good contact
Stick coil trouble
Spark plug incorrect
IC igniter in ECU trouble
Camshaft position sensor trouble
Neutral, starter lockout, or sidestand switch
trouble
Crankshaft sensor trouble
Ignition switch or engine stop switch
shorted
Wiring shorted or open
Fuse blown
Fuel/air mixture incorrect:
Bypass screw and/or idle adjusting screw
maladjusted
Air passage clogged
Air cleaner clogged, poorly sealed, or miss-
ing
Compression Low:
Spark plug loose
Cylinder head not sufficiently tightened
down
No valve clearance
Cylinder, piston worn
Piston ring bad (worn, weak, broken, or
sticking)
Piston ring/groove clearance excessive
Cylinder head gasket damaged
Cylinder head warped
Valve spring broken or weak
Valve not seating properly (valve bent,
worn, or c arbon accumulation on the
seating surface)
Poor Running at Low Speed:
Spark weak:
Battery voltage low
Spark plug dirty, broken, or maladjusted
Stick coil wiring trouble
Stick coil not in good contact
Spark plug incorrect
IC igniter in ECU trouble
Camshaft position sensor trouble
Crankshaft sensor trouble
Stick coil trouble
Immobilizer system trouble
Fuel/air mixture incorrect:
Bypass screw maladjusted
Air passage clogged
Air bleed pipe bleed holes clogged
Pilot passage clogged
Air cleaner clogged, poorly sealed, or miss-
ing
Fuel tank air vent obstructed
Fuel pump trouble
Throttle body assy holder loose
Air cleaner duct loose
Compression low:
Spark plug loose
Cylinder head not sufficiently tightened
down
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