Harley-Davidson Electronic Fuel Injection Tuner INSTALLATION Manual


Filed Under (Harley Davidson) by admin on 14-04-2012

Harley-Davidson Electronic Sequential Port Fuel Injection System, (ESPFI) This completely new engine management system was released starting with select 2001 model year Softail motorcycles. This system is a speed/density, open loop, sequential port fuel injection design that also controls spark timing and spark intensity. Speed/Density System – When the ECM monitors manifold air pressure, air temperature, throttle position and engine rpm to manage fuel delivery. Open Loop Control – When the ECM monitors sensors positioned on the intake side of the engine and does not monitor the end result of internal combustion at the exhaust. Sequential Port Fuel Injection – When the injector nozzle is positioned in the manifold near the intake valve and is precisely timed to deliver fuel to each cylinder. This ESPFI system is the exclusive design used on 2001 and Later EFI-equipped Softail models, 2002 and Later EFI-equipped Touring models, 2004 and Later Dyna models, and 2004 and later V-Rod models. Current ESPFI Components The following is a list of the major components of Harley-Davidson’s current ESPFI system. It is important to have an understanding of what these components do before learning how the ESPFI system functions. Refer to the appropriate Harley-Davidson Service Manual for the vehicle you are working on for additional information on component design and function and for the physical location and testing procedures for each individual component. ECM – Electronic Control Module – this is the brain of the system that collects input signals from multiple sensors, makes decisions and sends output signals to deliver fuel and spark to the engine. CKP – Crank Position Sensor – this sensor provides input signals to the ECM that indicate engine rpm, (how fast the engine is running in R evolutions P er M inute). The ECM also uses these inputs to determine what stroke the engine is in so it can deliver the fuel and spark at the desired time.