C
: Fuel system
a. Broken fuel pump
b. Dirty fuel filter
D
: Ignition system
a. Faulty spark plug
b. Broken coil
c. Broken shielded cap
E
: Intake circuit
a. Dirty air filter
b. Dirty by-pass circuit
c. Faulty Stepper motor
F
: Other
a. Incorrect timing
b. Wrong idle mixture
c.Incorrect reset of the throttle valve position sensor
2 MIU system faults may be caused by loose connectors. Make sure that all connections have been
correctly made.
Check the connections as follows:
A
check that the terminals are not bent.
B
check that the connectors have been properly connected.
C
check whether the malfunction can be fixed by shaking the connector slightly.
3 Check the entire system before replacing the MIUIf the fault is fixed by replacing the MIU control unit,
install the original control unit again and check if the fault occurs again.
4 When troubleshooting use a multimeter with an internal resistance over 10 Ohm /V. Instruments that
are not suitable might damage the MIU control unit. Instruments must be used with definitions over 0.1V
and 0.5 W , the precision must be greater than 2%.
1. Before fixing any part of the injection system, check to see if there are any registered faults. Do not
disconnect the battery before checking for faults.
2. The fuel feed system is pressurised at 250 kPa (2.5 BAR). Before disconnecting the fast-release
fitting of the power supply pipe, check that there are no naked flames. Do not smoke. Act with caution
to prevent spraying in the eyes.
3. When fixing electric components, operate with the battery connected only when actually required.
4. When functional checks are performed, check that the battery voltage is over 12V.
5. Before trying to start the vehicle, check to make sure there is at least two litres of fuel in the tank.
Failure to respect this norm will damage the fuel pump.
6. If the vehicle is expected to remain unused for a long time, refill the tank up to a little over half the
level. This will ensure the pump will be covered by fuel.
Injection
Vespa LX 125 - 150 i.e.
INJEC - 150
Summary of Contents for LX Series
Page 4: ......
Page 6: ...INDEX OF TOPICS CHARACTERISTICS CHAR ...
Page 21: ...INDEX OF TOPICS TOOLING TOOL ...
Page 33: ...INDEX OF TOPICS MAINTENANCE MAIN ...
Page 44: ...INDEX OF TOPICS TROUBLESHOOTING TROUBL ...
Page 48: ...Troubleshooting Vespa LX 125 150 i e TROUBL 48 ...
Page 49: ...INDEX OF TOPICS ELECTRICAL SYSTEM ELE SYS ...
Page 52: ...Components arrangement Electrical system Vespa LX 125 150 i e ELE SYS 52 ...
Page 86: ...INDEX OF TOPICS ENGINE FROM VEHICLE ENG VE ...
Page 90: ...Engine from vehicle Vespa LX 125 150 i e ENG VE 90 ...
Page 91: ...INDEX OF TOPICS ENGINE ENG ...
Page 137: ...Conceptual diagrams Vespa LX 125 150 i e Engine ENG 137 ...
Page 146: ...INDEX OF TOPICS INJECTION INJEC ...
Page 164: ...Injection Vespa LX 125 150 i e INJEC 164 ...
Page 171: ...Vespa LX 125 150 i e Injection INJEC 171 ...
Page 185: ...INDEX OF TOPICS SUSPENSIONS SUSP ...
Page 205: ...INDEX OF TOPICS BRAKING SYSTEM BRAK SYS ...
Page 214: ...INDEX OF TOPICS CHASSIS CHAS ...
Page 222: ...INDEX OF TOPICS PRE DELIVERY PRE DE ...
Page 226: ...INDEX OF TOPICS TIME TIME ...
Page 272: ...T Tank 256 Transmission 9 46 92 103 113 241 Turn indicators 65 Tyres 13 V Vehicle 8 87 88 ...