General information about the fuel system

The fuel system includes the fuel tank, fuel lines, fuel pump, filter, carburetor with air filter, or one of the fuel injection systems.

The main element of the fuel system is the carburetor or injection system, which is checked and adjusted at the factory for a specific engine and fuel type. Increased fuel consumption and reduced engine power are usually not a defect in the fuel system, but have other causes, among which driving style and driving conditions play a particularly important role. Therefore, in carburetors, it is only necessary to carefully adjust the idle system. Proper adjustment of the idle system has a significant impact on the operation of the engine in transient conditions up to medium engine speeds.

The fuel tank is located at the rear of the vehicle. The pump pumps fuel into the carburetor or fuel injection system. The performance of the pump exceeds the demand of the engine, and excess fuel is returned to the tank through the return pipeline, which eliminates the formation of vapor locks in the fuel lines.

The carbureted engines have two-barrel downdraft carburetors with automatic choke, Pierburg on OHC engines and Weber on DOHC engines.

On a Weber carburetor, the idle speed is controlled by a stepper motor.

Some models use the Bosch L-Jetronic fuel injection system. The system is controlled by the EECIV module (Electronic Engine Control Mk IV) (electronic engine control).