The information in this guide is for general knowledge and not a substitute for the complete Vialle LPi technical manual. For any installation, diagnostics, or repairs, consult a qualified LPG specialist.
A specialized LPG tank containing an internal pump that pressurizes the LPG.
Connect a pressure gauge to the fuel rail; monitor pressure during acceleration.
The liquid phase filter prevents microscopic debris from entering the high-tolerance components of the injection valves. This should be replaced every 30,000 to 50,000 km .
Because of the cooling effect and precise fuel delivery, engines converted with an LPi system suffer no power loss compared to gasoline, a common drawback of older vapor systems. Critical Component Overview lpi+vialle+technical+manual
When liquid LPG is injected into the intake port, it instantly vaporizes. This phase change from a liquid to a gas has a powerful cooling effect on the incoming air charge, effectively acting as an internal intercooler. This denser air charge allows for more efficient combustion, resulting in performance characteristics nearly identical to petrol and minimal power loss. The system is also designed to work effectively in extremely cold environments, with certification for operation at -40°C without requiring a reducer or vaporizer.
The fuel rail distributes liquid LPG to the individual injectors. At the end of the rail, a mechanical pressure regulator maintains a constant differential pressure across the system. It vents excess liquid fuel back into the return line, sending it straight to the tank. This continuous circulation keeps the fuel cool and prevents vapor lock. Vialle LPI Injectors
The pump circulates liquid LPG from the tank to the front of the vehicle at a pressure roughly 5 bars higher than the tank’s natural vapor pressure. This pressure boost ensures the fuel remains liquid even in a hot engine bay.
The system represents one of the most advanced LPG autogas technologies available for internal combustion engines. Unlike traditional vapor-phase systems, Vialle's technology injects liquid LPG directly into the intake manifold, offering superior performance, efficiency, and environmental benefits. The information in this guide is for general
: The system performs an electrical self-test; the dashboard LED blinks green.
| Code | Description | Technical Root Cause | Solution | |------|-------------|----------------------|----------| | P0170 | Lambda control out of range (lean) | LPG injector filter screen clogged (part no. VF-102) – differential pressure > 0.4 bar | Ultrasonic cleaning of injector nozzle | | P0215 | Fuel pump control circuit malfunction | PWM driver transistor short; or low battery voltage during startup (<10.5V) | Replace LPI pump ECU driver board | | P0444 | Evap system – LPG vapour leak | Liquid phase leak in engine bay – note: LPG vapour is heavier than air, collects in spark plug wells | Leak test with electronic sniffer; inspect injector O-rings (Viton, not standard rubber) | | U0100 | Lost communication with petrol ECU | CAN bus termination resistor mismatch (must be 120 ohms between CAN-H and CAN-L) | Re-crimp bus connectors; check for oxidation |
When liquid LPG escapes the injector nozzle, it enters the lower-pressure environment of the intake manifold. It instantly vaporizes (flashes). This phase change causes a rapid drop in temperature—an effect known as latent heat of vaporization.
A pressure increase of less than 2 bar points directly to a worn or failing PTC pump. 4. Maintenance and Repair Protocols Connect a pressure gauge to the fuel rail;
Comprehensive Guide to the Vialle LPi Technical Manual: Mastering Liquid Propane Injection
Note: For specific wiring diagrams, pinouts, and diagnostic trouble codes (DTCs), users should consult the official software suite (Vialle Diagnostic Tool) or service portals provided by authorized Vialle service partners.
If you need help diagnosing a specific error code or need guidance on a particular engine model layout, please specify the or the exact LED flash pattern you are seeing on your dashboard switch. Share public link