2-16
BF135A•BF150A
• ENGINE DOES NOT RUN SMOOTHLY
• Perform “g. ALERT SYSTEM” (P. 2-32) troubleshooting when the warning buzzer sounds.
Perform the following troubleshooting when the warning buzzer does not sound but the engine does not run smoothly.
Faulty spark plug.
Engine starts, but stalls
soon. Idle speed is not
stable or stalls.
Low pressure fuel system faulty.
Perform fuel supply system trouble-
shooting (P. 5-96).
High pressure fuel system faulty.
Perform fuel supply system trouble-
shooting (P. 5-96).
Idle control system faulty.
Perform idle control system trouble-
shooting (P. 5-93).
Secondary air being sucked.
• Loosely tightened IAC valve, dam-
aged gasket
• Loosely tightened throttle body,
damaged seal ring
• Loosely tightened intake manifold,
damaged seal ring
• Damaged fuel injector seal ring
• Loosely tightened injector base,
damaged gasket
• Retighten the IAC valve. Replace
the gasket if damaged (P. 5-95).
• Retighten the throttle body.
Replace the seal ring if damaged
(P. 5-131).
• Retighten the intake manifold (P.
• Replace the fuel injector O-ring if
• Retighten the injector base.
Replace the gasket if damaged
(P. 5-139).