Sym ATTILA RS-21 EFi 150 Service Manual page 51

4. FUEL INJECTION SYSTEM
Engine cannot be started or difficult to start.
Does the warning lamp goes
on for 2 seconds and then
off?
Is the warning lamp out of
order?
Is the fuel system abnormal?
Is the electrical circuit
abnormal?
Is the engine abnormal?
4-6
This chapter Contents
Cannot be started or
difficult to start
NG
OK
NG
OK
NG
OK
NG
OK
NG
OK
END
1.
Check electrical circuit according to
procedure.
1. Connect the Data Scan and check
EMS trouble content.
2. Trouble shooting according to the
troubleshooting procedure.
1. Low fuel in fuel tank.
2. The fuel pressure of the injector is
lower than 2.5bar.
3. Fuel leaking in pipe?
4. abnormal regulator?
5. Fuel pump pile leaking?
6. abnormal fuel pump?
7. abnormal fuel injector?
1. No spark on the spark plug?
2. wet spark plug?
3. Loosen spark plug cap?
4. short in RPM sensor?
5. Loosen high voltage cable?
6. No connection for the by-pass valve?
7. abnormal ECU?
8. Clean the throttle valve body and
ECU does not be set-up?
1. No valve clearance?
2. Incorrect ignition timing?
3. Stuck valve?
4. worn out cylinder and piston ring?
5. improperly adjustment of the air
adjustment screw onto the throttle
valve body?