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Home >> GMC >> 1991 >> Forward Control 6.2 J, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 4 (Engine Controls - System/Component Tests) >> Fuel System (Diesel) >> Injectors >> Spray Pattern Test
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Spray Pattern Test

WARNING: This page does not describe the selected car, but rather 35 other vehicles, including the 1992 Pontiac Trans Sport, 1992 Oldsmobile Silhouette, 1992 Oldsmobile Bravada, 1992 GMC Yukon, and 1992 GMC Vandura Special. However, it is still accessible from the selected car via links, so may be relevant.

The injector nozzles used with this system have several features that make pattern testing difficult. These features include longer nozzle overlap, greater pintle-to-body clearances and an internal wave washer between injector nozzle nut and injector. Typical injector nozzle tester cannot deliver fuel with sufficient velocity to obtain proper spray patterns. DO NOT  replace injector nozzle(s) based on spray pattern.