Idle Control System - Honda BF40D Mode D'emploi

8. IDLE CONTROL SYSTEM

• TROUBLESHOOTING
When the MIL does not come ON but an engine failure
showing any of the following symptoms occurs, inspect
the system(s) and part(s) in the numbered sequence.
• Hard to start
1. IAC valve (P. 5-75)
2. Pressure regulator control tube
• Engine starts but stalls soon
1. Idle adjusting screw
2. IAC valve (P.5-75)
3. Pressure regulator control tube
• Engine speed is higher than the specified idle speed
after warming up.
1. Idle adjusting screw
2. IAC valve (P.5-75)
3. Pressure regulator control tube
• Engine speed is higher than the specified trolling
speed after warming up.
1. Neutral switch (P. 18-17)
2. IAC valve (P. 5-75)
3. Idle adjusting screw
4. Pressure regulator control tube
• Engine speed is lower than the specified idle speed
after warming up.
1. IAC valve (P. 5-75)
2. Idle adjusting screw
3. Pressure regulator control tube
• Engine speed is lower than the specified trolling speed
after warming up.
1. IAC valve (P. 5-75)
2. Idle adjusting screw
3. Pressure regulator control tube
• Engine speed is not stable during idle and trolling.
1. IAC valve (P. 5-75)
2. Idle adjusting screw
3. Pressure regulator control tube
4. Neutral switch (P. 18-17)
5-73
• Idle Adjusting Screw Adjustment
Perform idle speed adjustment before adjusting the idle
adjusting screw (P. 3-16).
Adjustment with HDS (Dr. H or pocket tester)
1) Disconnect the 4P connector (Red) and connect the
HDS (Dr. H or pocket tester) to the DLC (Data Link
Connector) (P. 5-12).
2) Set the SCS mode using the HDS (Dr. H or pocket
tester).
See the HDS operation instructions for how to use it.
3) Release the breather tube from the tube clamp.
4) Disconnect the IAC valve 2P connector. (The MIL
should come ON.)
TUBE CLAMP
5) Check the idle speed with the HDS (Dr. H or pocket
tester).
Idle speed
(at neutral)
If the measurement is outside the specification,
remove the cap and adjust the idle speed by turning
the idle adjusting screw.
CAP
468
BREATHER TUBE
IAC VALVE 2P CONNECTOR
-1
700 30 min (rpm)
IDLE ADJUSTING SCREW