Sym Citycom.300i Service Manual page 19

1. GENERAL INFORMATION
C. Engine runs sluggish (especially in low speed and idling)
Check and adjustment
Check ignition timing
(using ignition lamp)
Normal
The gasket of the throttle
body has air to suck or not
Have not sucked the air
Remove spark plug, install
spark plug into spark plug
cap and perform spark test
against engine ground
Good spark
D. Engine runs sluggish (High speed)
Check and adjustment
Check ignition timing
Normal
Check the fuel pump supply
situation
good
Check if fuel injector clogged
Normal
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To this chapter contents
Fault condition
Abnormal
Suck the air
Poor
Fault condition
Abnormal
poor
Clogged
Probable causes
Incorrect ignition timing (malfunction of ECU or
AC generator)
1. damage the insulator gasket.
2. Throttle body wrongly attached
3. Inlet pipe gasket abnormal
4. ABV pipe cracked
Spark plug fouled
Malfunction of E.C.U.
Malfunction of AC generator
Malfunction of ignition coil
Open or short circuit in spark plug leads
Malfunction of main switch
Probable causes
Malfunction of ECU.
Malfunction of AC generator
Insufficient fuel in fuel tank
Fuel filter clogged
Restricted fuel tank vent
1. change the fuel injector