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Fuel Injection System - 6.2L Diesel: Description

General Motors 6.2L engine uses a mechanical high pressure rotary pump, gear driven by camshaft at camshaft speed. It injects a precisely metered amount of fuel to each cylinder at the proper time.

A mechanical fuel pump, mounted on right of engine, pulls fuel from fuel tank through a primary filter. Fuel is pumped through a secondary filter mounted on firewall (pickups) or rear of air cleaner (vans) to the injection pump. High pressure fuel lines carry fuel from pump to 1 injection nozzle in each cylinder. All fuel lines are the same length to ensure that there is no variance in timing. Engine RPM is controlled by a rotary fuel metering valve. As accelerator pedal is pushed down, throttle linkage opens metering valve to allow increased fuel delivery.

Fig 1: Diesel Injection System Fuel Circuit
G8722
NOTE: Secondary fuel filter is mounted on firewall (pickups) or rear of air cleaner (vans).