Fuel System - General Information: Specifications Jaguar X-type I рестайлинг

Specifications

General Specifications

Torque Specifications

Scheme 10

The mechanical returnless fuel system utilized has the following advantages

1. Reduces the build up of fuel pressure on starting the engine
2. Holds the pressure in the fuel lines to aid engine hot starts
3. Smooths out pulsations and reduces fuel pump noise

The fuel tank is constructed of high density polyethylene and is located underneath the vehicle below the rear passenger seat. The tank is retained by two support straps fixed to the vehicle's underbody, with the underside of the tank being protected by a fitted heatshield.

The electric turbine fuel pump, which operates in a fuel reservoir, has an integral top plate for the external pipe work and electrical connectors. The pump is secured to the fuel tank by a screw-on plastic closure ring.

Two roll over valves are connected by a hose which allows air to circulate in the tank which prevents the build up of high pressure vapor areas which may be created during fuel tank filling on gradients or when the vehicle is in motion.

Fuel is pumped from the tank to the fuel rail at a constant pressure of 4.5 bar, regardless of the amount of fuel being injected into the engine. Fuel pressure is constantly maintained by the fuel pump's integral mechanical pressure regulator which returns excess fuel to the fuel tank via a T-piece positioned directly after the fuel filter.

Scheme 11

The electronic returnless fuel system utilized has the following advantages

1. reduced fuel tank vapor.
2. requires less electrical power.
3. does not require a fuel return line.

The intelligence of this system is contained within the engine control module (ECM).

The ECM determines the required fuel flow and communicates this information to the fuel pump controller. The fuel pump controller has the fuel pump driver functions fully integrated into the microprocessor. The ECM calculates the frequency and determines the current required by the fuel pump to maintain the correct fuel pressure at the fuel injectors.

The fuel tank is of a saddle design which incorporates two sender units. The right-hand side houses the fuel pump module. The left-hand side houses the transfer pump (jet pump) module.

Fuel is supplied at high pressure to the injectors via a fuel rail which incorporates a fuel pressure and a fuel temperature sensor. The ECM increases the fuel pressure to minimize fuel vapor formation to maintain fuel flow across the injectors. An inertia type fuel cut-off switch will cut power to the fuel pump module in the event of an accident.

Scheme 12

The fuel tank is constructed of high density polyethylene and is located underneath the vehicle below the rear passenger seat. The tank is retained by two support straps fixed to the vehicle's underbody, with the underside of the tank being protected by a fitted heatshield.

The fuel sender unit uses a resistor tile and float rod system to supply information to the instrument cluster of the fuel level. The fuel system has a run dry strategy which leaves four liters of unusable fuel in the tank. If fuel runout occurs no system priming/bleeding is required.

The fuel filter is located at the top of the bulkhead on the right-hand side of the vehicle. The fuel filter incorporates a fuel pre heat function, which utilizes a ball valve operated by a bimetallic strip. When the temperature is less than 15° C (59° F), the ball valve allows the warm fuel in the fuel return system to pass back through the fuel filter to the fuel pump to improve cold running. Once the temperature exceeds 31° C (88° F) a bimetallic strip closes the ball valve in the fuel filter and all of the fuel in the fuel return system is directed back to the fuel tank.

See also:
• Lifting