Fuel Injectors
Based on information from various sensors, the ECM measures the fuel injection amount. The fuel injector is a solenoid-operated valve that meters the fuel flow to each combustion cylinder. The fuel injector is opened and closed a constant number of times per crankshaft revolutions. The amount of fuel is controlled by the length of time the fuel injector is held open. The fuel injector is normally closed, and is operated by a 12-volt source from either the ECM power relay or the fuel pump relay. The ground Signal is controlled by the ECM.
The Gasoline Direct Injection (GDI) system injects high pressure fuel directly into the combustion chamber. The high pressure injectors have an internal swirl disk which rotates with fuel flow to help atomize the discharging fuel. This causes the fuel to evaporate rapidly, which reduces inlet air temperature. This cooler atomized air/fuel inlet charge increases power output. Each high pressure injector is connected to ECM with 2 lines. First line is high pressure side and second line is low pressure side. If any line of these two connections is short to battery or ground, ECM sets DTC.