Honda CBF150 2002 Manual page 78

FUEL SYSTEM
TROUBLESHOOTING
Engine won't start
• Too much fuel getting to the engine
– Air cleaner clogged
– Flooded carburetor
• Intake air leak
• Fuel contaminated/deteriorated
• No fuel to carburetor
– Fuel strainer clogged
– Fuel hose clogged
– Fuel valve stuck
– Float level misadjusted
Lean mixture
• Fuel jet clogged
• Float valve faulty
• Float level too low
• Fuel line restricted
• Intake air leak
• Throttle valve faulty
Rich mixture
• Choke valve in close position
• Float valve faulty
• Float level too high
• Air jets clogged
• Flooded carburetor
Engine stall, hard to start, rough idling
• Fuel line restricted
• Ignition system malfunction
• Fuel mixture too lean/rich (pilot screw adjustment)
• Fuel contaminated/deteriorated
• Intake air leak
• Idle speed misadjusted
• Float level misadjusted
Afterburn when engine braking is used
• Lean mixture in slow circuit
• Faulty PAIR control valve
• Faulty PAIR check valve
• Clogged hose of the PAIR system
• Ignition system malfunction
Backfiring or misfiring during acceleration
• Ignition system malfunction
• Fuel mixture too lean
Poor performance (driveability) and poor fuel economy
• Fuel system clogged
• Ignition system malfunction
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