Gilera 633721 Workshop Manual page 199

Nexus 500 euro 3
Possible Cause
Ignition efficiency
Correctness of the parameters
Intake system cleaning
Intake system sealing (infiltrations)
Fuel feed (low pressure)
Analysis of exhaust fumes before the catalytic converter
Engine does not rev down
ENGINE DOES NOT RETURN TO THE IDLING SPEED/IDLING SPEED TOO HIGH
Possible Cause
Presence of faults detected by the self diagnosis
Ignition efficiency
Correctness of the parameters
Intake system sealing (infiltrations)
Fuel feed (low pressure)
Analysis of exhaust fumes before the catalytic converter
Exhaust backfires in deceleration
Possible Cause
Presence of faults detected by the self diagnosis
EXHAUST BACKFIRES WHEN DECELERATING
Operation
Air temperature
Coolant temperature.
Atmospheric pressure
Spark plug
Ignition timing
Throttle valve position sensor
Stepper
Coolant temperature sensor
Intake air temperature sensor
Air filter
Diffuser and throttle valve
Additional air pipe and Stepper
Intake manifold - head
Throttle body - manifold
Intake sleeve
Filter box
Fuel pump
Pressure regulator
Fuel filter
Injector capacity
Trimmer value adjustment (CO % adjustment)
Operation
Pump relay
H.V. coil
Injector
revolution timing sensor
Air temperature
Coolant temperature.
Atmospheric pressure
Ignition timing
Throttle valve position sensor
Stepper
Coolant temperature sensor
Intake air temperature sensor
Intake manifold - head
Throttle body - manifold
Intake sleeve
Filter box
Fuel pump
Pressure regulator
Fuel filter
Injector capacity
Trimmer value adjustment (CO % adjustment)
Operation
Pump relay
Injection
INJEC - 199