Fuel Injection System - HONDA PGM-FI: Description
There are 4 sub-systems in the PGM-FI (Programmed Fuel-Injection) system: air intake system, electronic control system, idle control system, and fuel delivery system. The electronic control system is covered in COMPUTER CONTROLS section. The idle control system is covered in TUNE-UP section. The other 2 systems, air intake and fuel delivery, are covered here.
The system uses an 8-bit microcomputer and various sensors to provide accurate control of air/fuel mixture under all operating conditions. At the precise time a piston is on its intake stroke, fuel is injected into the correct intake manifold runner (sequential injection).