Sequential injection system LPG: engine kit
The "phased sequential" system is the last generation of injection LPG and CNG systems suitable for installation both in multipoint injection sequential vehicles and in multipoint injection "semi-sequential" and "full-group" vehicles.
It is the most effective system that ensures the best results in terms of driving conditions and performance.
The enriching strategies and consumption and emissions optimisation strategies generated by the petrol CPU are indeed unaltered in each cylinder.
This system is compatible with the originaI OBD system (On Board Diagnosis) of the vehicle. The OBD system informs the user if any of the vehicle components dedicated to reducing pollutant emissions may compromise the actual emissions. If this should occur I the user would be informed via a buzzer built-in the change-over switch and the installer can easily find the problem by connecting the system to dedicated instruments.
DESCRIPTION OF THE LPG SEQUENTIAL KIT
LPG in its liquid state reaches the regulator-vaporiser ( 1 ) through the LPG solenoid valve ( 2 ) fitted on the regulator-vaporiser, which is only open when the vehicle is running on gas. The LPG is vaporised inside the regulator-vaporiser and its pressure is reduced. From the regulatorvaporiser the LPG in its gaseous state reaches the rail of injectors ( 3 ) at a positive pressure compared to the vacuum inside the in-take manifolds. The top chamber of the regulator I inside which a calibration spring is fitted, is connected by a tube to the in-take manifold.
There are gauged nozzles on the rail of injectors which are connected to the nozzles ( 4 ) of the in-take manifold by rubber hoses, which inject gas into the engine.
The Sequential system for LPG is a specific one for catalyst vehicles and therefore has an ECU ( 5 ) that commands the gas electro-injectors in the rail, guaranteeing the perfect stoichiometric ratio of the mix by processing the signal of the pressure sensor ( 6 ) and the injection timing of the petrol injectors. When the vehicle is running on gas, the switch-over to petrol is intercepted by an electronic device (emulator) built-in the actual ECU, which cuts-out the original petrol electro-injectors.
The user can choose which fuel to use (LPG or PETROL) using the change-over switch ( 7 ) fitted in a handy position inside the vehicle compartment. The change-over switch comes complete with fuel indicator .
LPG G/SEQUENTIAL REGULATOR
The LPG regulator-vaporizer is the single-stage type with diaphragm and is compensated by the vacuum of the suction manifold. It is designed to ensure a higher output pressure than the pressure inside the suction pipes of the engine. The engine coolant flows inside the regulator-vaporizer so that the LPG is completely vaporized. A solenoid valve complete with filter is fitted on the inlet of the regulator. A temperature sensor and a safety valve are fitted on the first stage .
SELF-ADAPTING AND SELF-LEARNING ELECTRONIC UNIT FOR "PHASED" SEQUENTIAL SYSTEM
The electronic control unit of the multipoint sequential system directly processes the injection timing of the original petrol injectors, transforming it into injection timing for the gas injectors. In this way the strategies defined by the vehicle manufacturer are guaranteed in terms of driving conditions and emissions.
Even with the passing of time, a better performing and more efficient vehicle gas running is allowed by the self-adaping and self-learning strategies of the ECU.
Those strategies make the ECU self-adapt according both to the engine getting "older" and to the ever changing fuel characteristics.
While self-learning it memorizes the new values and turn them into reference values for gas injection control.
The characteristics of the ECU are such that it is easily and rapidly calibrated when installing the system.
It adapts the injection timing to the driving conditions and to the environmental conditions. It is equipped with an effective and functional diagnosis system and is pre-arranged to meet OBD norms.
The ECU also offers the following functions:
- Possibility to automatically switch from petrol to gas in acceleration or deceleration.
- Possibility to choose the engine rpm at which the system is to switch from petrol to gas.
- Pre-arrangement for most Italian and Foreign level sensors.
- Pre-arrangement for reading all Lambda probes.
- Pre-arrangement for automatically switching back to petrol in the case of system anomalies or if the fuel should run out (LPG/CNG) in the tank or cylinder
- Pre-arrangement for analysing the anomalies recorded and to auto-diagnose itself.
- Pre-arrangement for analysing the need to service the vehicle with relative display of the hours that vehicle has run on gas.
RAIL OF INJECTORS
The rail sequentially dispenses the gas to each cylinder. This function is performed by separate and absolutely independent injectors, which receive the electric signal from the ecu. This signal enables the system to calibrate the amount of gas that is injected in just the cylinder in the suction phase and it also controls the cut-off function.
SWITCH UNIT
This very small electronic module is installed inside the vehicle compartment in a handy position for the driver. Thanks to its very small size it can be fitted in the place of an empty switch on the dashboard or a hole can be punched for it on the dashboard using a hot punch. The switch unit has the following functions: - It acts as a 2-position gas/petrol selector switch and indicates the fuel in use by means of two LED's: A yellow one is lit when running on gas and a red one is lit when running on petrol. - It displays the amount of gas in the tank/cylinder by means of five LED's: four green ones (1/4; 1/2; 3/4 and 4/4) and a red one for reserve. - It informs the driver on any anomalies encountered in the Etagas system by means of the red petrol LED that starts to flash.
FILTER
The filter is fitted between the regulator and the rail in the gaseous section. It holds back any solid, oily or other particles that may compromise the efficiency of the rail of injectors in time.
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