Sym Joyride 125 Service Manual page 23

1. GENERAL INFORMATION
C. Engine runs sluggish (especially in low speed and idling)
Check and adjustment
Check ignition timing
(using ignition lamp)
Normal
Check for any air sucked in through
the throttle body insulator gasket
No air sucked in
Remove the spark plug and
check the spark condition
Good spark
D. Engine runs sluggish (High speed)
Check and adjustment
Check ignition timing
Normal
Check the fuel pump
supply condition
Good
Check if fuel injector clogged
Normal
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To this chapter contents
Fault condition
Abnormal
Air sucked in
Poor spark
Fault condition
Abnormal
Poor
Clogged
Probable causes
1. Incorrect ignition timing (malfunction of
ECU or AC Generator)
1. Abnormal throttle body insulator gasket.
2. Abnormal throttle body installation
3. Abnormal inlet pipe gasket
4. Damaged ABV pipe
1. Contaminated spark plug
2. Malfunction of ECU
3. Malfunction of AC Generator
4. Malfunction of ignition coil
5. Open or short circuit in spark plug
leads
6. Malfunction of main switch
Probable causes
1. Malfunction of ECU
2. Malfunction of AC Generator
1. Insufficient fuel in the fuel tank
2. Pressed or clogged fuel pipe
1. Replace the fuel injector