Fuel Injectors

A fuel rail links the fuel pressure regulator with the fuel injectors. Each cylinder is provided with a solenoid-operated injector which sprays fuel towards back of each inlet valve. Each injector is energized through the ignition coil and grounded through the ECU to complete the circuit.

Each injector is linked to a resistor to reduce operating voltage to 3 volts and to protect injectors from power surges (except TR7 models). Resistors for Jaguar models are located in a single unit mounted on right side of firewall; TR8 resistors are located between ECU and injectors.

The ECU controls the length of time each injector is open. The "open" time of the injector governs the amount of fuel delivered. The injectors deliver 1/2 the amount of fuel required for 1 operating cycle each time they spray (twice per cycle).