Poor Performance At Low And Idle Speed - Honda GL1800 Service Manual

POOR PERFORMANCE AT LOW AND IDLE SPEED

1. Intake Manifold Gasket Inspection
Check for leaking intake manifold gasket.
Is the intake manifold gasket leaking?
YES
NO
2. Spark Test
Perform spark test.
Is the spark quality good?
NO
YES
3. Ignition Timing Inspection
Check the ignition timing.
Is the ignition timing as specified?
NO
YES
4. Programmed Fuel Injection System Inspection
Check the fuel injection system.
Is the fuel injection system normal?
NO
– • Loose intake manifold mounting bolts
• Damaged intake manifold gasket
– GO TO STEP 2.
– • Faulty spark plug
• Fouled spark plug
• Loose ignition system wires
• Broken or shorted spark plug wire
• Faulty ignition pulse generator
• Faulty ignition coil
• Faulty engine control module (ECM)
– GO TO STEP 3.
– • Faulty engine control module (ECM)
• Faulty ignition pulse generator
– GO TO STEP 4.
– Faulty fuel injection system (section 5)
TROUBLESHOOTING
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