Gilera Fuoco 500 - Engine Does Not Rev down; Exhaust Backfires in Deceleration

Possible Cause Operation
Fuel filter
Injector capacity
Engine does not rev down
ENGINE DOES NOT RETURN TO THE IDLING SPEED/IDLING SPEED TOO HIGH
Possible Cause Operation
Presence of faults detected by the self diagnosis Pump relay
HV coil
Injector
revolution timing sensor
Air temperature
Coolant temperature.
Ignition efficiency Ignition timing
Correctness of the parameters Throttle valve position sensor
Stepper
Coolant temperature sensor
Intake air temperature sensor
Intake system seal (infiltrations) Intake manifold - head
throttle body - manifold
Intake manifold
Filter box
Fuel feed (low pressure) Fuel pump
Pressure regulator
Fuel filter
Injector capacity
Exhaust backfires in deceleration
EXHAUST BACKFIRES WHEN DECELERATING
Possible Cause Operation
Presence of faults detected by the self diagnosis Pump relay
HV coil
Injector
revolution timing sensor
Air temperature
Coolant temperature.
Lambda sensor
Correctness of the parameters Throttle valve position sensor
Stepper
Coolant temperature sensor
Intake air temperature sensor
Intake system seal (infiltrations) Intake manifold - head
throttle body - manifold
Intake manifold
Filter box
Fuel feed (low pressure) Fuel pump
Pressure regulator
Fuel filter
Injector capacity
Exhaust system seal (infiltrations) Manifold - cylinder head
Manifold - muffler
Injection Fuoco 500 i.e.
INJEC - 10