Acceleration enrichment control

(Continued)

ACCELERATION ENRICHMENT CONTROL

The ECU detects full load conditions according to signal from the following:

• throttle position potentiometer
• absolute pressure sensor

According to this information, the ECU performs the following strategies:

• it increases basic injection time
• it disables the lambda sensor.

FUEL CUT-OFF DURING RELEASE

When the accelerator pedal is released and the throttle is closed, the ECU cuts off the fuel. Fuel feed is started again before the engine reaches idling speed according to the following:

• engine rpm
• coolant temperature
• intake air temperature

FUEL FUME RE-CIRCULATION

Fuel fumes (pollutants) are collected in an active carbon filter (canister) and sent through the intake manifolds to be burnt.

This is controlled by means of a solenoid valve controlled by the ECU only when engine running conditions allow.

The ECU, in fact, compensates the amount of supplementary fuel by reducing feed to the injectors.

(Cont.)