Modern cars are often equipped with direct fuel injection engines. These power units are about 20% more fuel-efficient than traditional atmospheric engines, but vehicle owners still seek ways to reduce fuel costs further by installing an LPG system. Until recently, installing LPG in direct injection engines was a complicated task. However, now certified services, such as gaz-time.pl, successfully perform installations even in turbocharged engines. In this article, we will explain the challenges that can arise when installing LPG in direct injection engines.
Characteristics of Direct Injection Engine Systems
Direct fuel injection engines have several key features:
- Fuel is injected at high pressure (3-11 MPa) directly into the combustion chambers of the cylinders, rather than into the intake manifold as in the case of indirect injection.
- The air-fuel mixture forms directly in the engine cylinders, where air is supplied separately and the gasoline is atomized.
- Depending on the engine load, the system forms three types of air-fuel mixtures:
- Layered mixture with more air at low load.
- Stoichiometric mixture at medium load (fuel to air ratio of 1:14.7).
- Homogeneous mixture with minimal air at high loads.
The process of mixture formation is controlled by electronic engine control systems (ECU), which allows the engine to operate efficiently in different modes and save fuel. However, the complex algorithms controlling the direct injection system create additional challenges when installing an LPG system.
Challenges with Installing LPG in Direct Injection Engines
The main issue when installing LPG in a direct injection engine is protecting the gasoline injectors. These injectors are located directly in the combustion chamber, where they are exposed to high temperatures. Under normal conditions, they are cooled by gasoline. If the gasoline supply is cut off while running on gas, the injectors can overheat and get damaged. There are two ways to solve this problem:
- Installation of a 6th generation LPG system
This system uses the liquid phase of LPG, which is supplied to the combustion chambers through the gasoline injectors. This allows for the complete elimination of gasoline, maintaining the cooling effect for the injectors. However, this solution has some downsides:- High installation cost.
- Increased risk of pump failure when using low-quality gas.
- Installation of a 4th generation LPG system
This option involves supplying gas in its gaseous phase through dedicated LPG injectors, with some gasoline still being supplied to the engine for injector cooling. The fuel consumption of gas and gasoline typically ranges from 80:20 to 95:5. This is a more affordable option and is widely used in Ukraine for converting direct injection vehicles to gas.
Additional Challenges When Installing LPG
In addition to protecting the injectors, there are several other factors that can complicate the installation and gas regulation in the car https://gaz-time.pl/regulacja-lpg in direct injection engines:
- Equipment compatibility: Each engine requires a specific LPG kit because direct injection systems vary in design. For example, the types of injectors, their placement, and the operating modes of the ECU differ.
- System calibration: Installing LPG in a direct injection engine requires precise ECU software calibration to ensure correct operation between the gasoline and gas injectors. Improper calibration can lead to reduced engine performance or increased fuel consumption.
- Injector system load: It’s important to remember that with partial gasoline supply, the load on the gasoline injectors still exists, though it is less than when running exclusively on gasoline. This means regular maintenance of the injectors is still necessary, even when the vehicle is running on gas.
Conclusion
The installation of a 4th generation LPG system remains the most popular solution for cars with direct fuel injection systems in Ukraine. These systems have already proven their effectiveness and economic viability. To get accurate advice on installing LPG in your car, it is advisable to contact the Gaz Time service network in Warsaw, where we will help you select the optimal kit and professionally install the system.
