Fuel Injection System - 6-CYL Diesel: Operation: Injectors
Fuel injectors are a liquid-controlled, throttling pintle, nozzle-type. Injectors components consist of a nozzle holder, nozzle (and needle), and a fuel return port.
Initially, the injectors spray a small portion of fuel into turbulence chamber, which vaporizes and ignites. As needle continues to lift from its seat, remainder of fuel is injected and combustion continues. This form of injection reduces engine knock.
A special instrumented injector replaces normal 5th cylinder injector. This injector has an electric coil and 2 outlet wires. See Fig 1 .
The instrumented injector is slightly longer than normal injectors, and its injection line is slightly shorter than normal injector lines. Each time nozzle needle moves, a signal is sent to tripminder computer (for mileage calculation).
A 2nd instrumented injector is installed at 4th cylinder. Fuel flow information from this injector is sent to trunk-mounted electronic control system, which alters pump timing to control emissions.