Poor Performance At Low And Idle Speed - Honda 1998 VT750C Service Manual

TROUBLESHOOTING
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11. Check for engine overheating
I
Not overheating
Possible cause
- - - - - - - Overheating
------1~~
.
Coolant level low
• Fan motor not working (faulty fan
motor switch)
• Thermostat stuck close
• Excessive carbon build-up in
combustion chamber
• Use of poor quality fuel
• Clutch slipping
• Lean fuel mixture
• Wrong type of fuel
12. Accelerate or run at high speed
~
Engine does not knock
- - - - - - - Engine knocks
-------I~~
•
Worn piston and cylinder
• Wrong type of fuel
• Excessive carbon build-up in
commbustion chamber
• Ignition timing to advanced
(faulty ignition control module)
• Lean fuel mixture
POOR PERFORMANCE AT LOW AND IDLE SPEED
Possible cause
1. Check carburetor pilot screw adjustment - - - Incorrect -------~~ • See section 5
I
Correct
+
- - - - - - - - - - - - Weak or intermit- ----t~~
•
Faulty carbon or wet fouled spark
tent spark plug
• Faulty ignition control module
• Faulty ignition coil
• Broken or shorted spark plug wire
• Faulty engine stop switch
• Faulty ignition pulse generator
• Faulty ignition switch
• Loose or disconnected ignition
system wires
2. Check for leaking intake pipe - - - - - - - - Leaking
--------t~~
.
Loose insulator clamps
I .
Damaged insulator
Not leak
+
3. Perform spark test
I
Good spark
r
1
4. Check ignition timing - - - - - - - - - - Incorrect --------t.~
.
Improper ignition timing (faulty
ignition control module)
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