Fuel Injectors
The PFI Fuel Injector Assembly, is a solenoid-operated device, controlled by PCM, that meters pressurized fuel to a single engine cylinder. See Fig 1 . The PCM energizes injector solenoid raising injector pintle. Pressurized fuel flows through an opening at end of injector, around pintle tip, creating a conical spray pattern of finely atomized fuel. The position of injector in intake manifold directs fuel spray at back side of intake valve. The fuel is further atomized before entering cylinder combustion chamber.
A fuel injector which does not open would cause a lack of power or a no-start condition. An injector which is stuck partly open or leaking could cause loss of pressure after key off: long crank times would be noticed on some engines. Also, a leaking injector may cause dieseling because some fuel could be delivered to engine after key is turned "OFF."