How does a return style fuel injector system work?
How does a return style fuel injector system work?
Return style systems hold a big advantage in that with a vacuum/boost referenced fuel pressure regulator, the system can maintain a CONSTANT effective fuel pressure, which can extend the range of fuel injectors and help them function at lower fuel demands as well.
How is the pulsewidth calculated for a GM injector?
GM uses manifold pressure to subtract away from the rail pressure (which it always assumes is 58psi) to calculate pulsewidth. By referencing the flow rate table, in which the flow rate at various effective pressures is programmed in, the PCM knows what flow the injector is capable of at any given operating system.
What happens when the fuel injector is dirty?
When the tip of the fuel injector is dirty, it clogs the small holes that supply fuel into the combustion compartment, causing the poor acceleration. The fuel pressure regulator is in the fuel system to control the pressure of fuel that gets to the engine.
What is the effective fuel pressure in a naturally aspirated engine?
By contrast, when a naturally aspirated engine is wide open throttle, the manifold pressure is not in vacuum or in boost, so the effective pressure is the 58psi of rail pressure and nothing more. However, a boosted engine at 10psi will be resisting the fuel, causing effective pressure to drop to 48psi from the 58psi in the rail.
Is the fuel pressure regulator connected to the manifold vacuum?
Typical aftermarket manifold referenced fuel pressure regulator. For many applications, the fuel pressure regulator is not connected to manifold vacuum. This is very popular in naturally aspirated engines. Instead, the engine calibration is tuned to accommodate a near constant/static change in fuel pressure.
Return style systems hold a big advantage in that with a vacuum/boost referenced fuel pressure regulator, the system can maintain a CONSTANT effective fuel pressure, which can extend the range of fuel injectors and help them function at lower fuel demands as well.
GM uses manifold pressure to subtract away from the rail pressure (which it always assumes is 58psi) to calculate pulsewidth. By referencing the flow rate table, in which the flow rate at various effective pressures is programmed in, the PCM knows what flow the injector is capable of at any given operating system.
By contrast, when a naturally aspirated engine is wide open throttle, the manifold pressure is not in vacuum or in boost, so the effective pressure is the 58psi of rail pressure and nothing more. However, a boosted engine at 10psi will be resisting the fuel, causing effective pressure to drop to 48psi from the 58psi in the rail.
