The petrol injection system senses the changes to the influencing parameters, pass the information to a central co-ordinating mechanism, which then integrates these individuals signals and interprets the fuel requirements. The resultant needs are then transmitted by hydraulic, mechanical and electrical means to the pumping and metering devices, which then supply the correct quantity of fuel to the induction for the particular operating conditions
When the vehicle is running on natural gas, the signals transmitted are different from those which are send when the car is running on petrol. These signals are interpreted as faults by the electronic control unit (ECU) and the light “CHECK-ENGINE” turns on in the dashboard. To prevent the ECU from reading those wrong signals, devices called Emulators are used. Moreover, to improve the car performance a Timing Advance Processor must be installed.

Lambda sensor emulator
This device sends to the ECU a modified signal, which is interpreted as normal petrol one.

Injector emulator
This device is used to cut the injector activation signal, in order to avoid mixing the fuels. In addition, it is no longer necessary to control the injectors polarization because the signal is cut and simulated individually to each injector. Moreover, two types of these emulators exist.

• Multipoint injector emulator: When the injectors are positioned in each induction manifold branch pipe just in front of the inlet pipe, a multipoint injector emulator must be used.

• Single point injector emulator: This type of emulator is used in vehicles where the engine is fed by one injector.

Timing advance processor
Due to the fact that natural gas has different thermodynamic properties, the timing must be modified in order to adapt it to the new fuel.

Anticontaminating system
In these equipments the valve register screw is replaced by a valve drives by a stepper motor that allows or does not allows natural gas to enter the mixer. This motor is governed by a module, which in turn receives the signal of the lambda sensor, which shows the presence of oxygen in exhaust gases. The system works balancing the mixture constantly in order to reduce the level of contaminating emissions.

AVE 03
Is an Integrated System where the timing advance processor, the injector emulator, the lambda sensor emulator, an anticontaminating system, CNG level sensor and fuel selector switch are included.

						Anti contaminating system Electronic Control Module Fuel selector swith ANTICONTAMINATING SYSTEM
Lambda sensor emulator		Injector emulator		Timing advance processor