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Fuel Injector Balance Test With Special Tool: Description

The scan tool is first used to energize the fuel pump relay. The fuel injector tester is then used to pulse each injector for a precise amount of time, allowing a measured amount of fuel into the manifold. This causes a drop in system fuel pressure that can be recorded and used to compare each injector. See FUEL INJECTOR BALANCE TEST EXAMPLE (TYPICAL)  table.

FUEL INJECTOR BALANCE TEST EXAMPLE (TYPICAL)

Condition Cylinder No. 1 Cylinder No. 2 Cylinder No. 3 Cylinder No. 4
1st Reading 43 psi (296 kPa) 43 psi (296 kPa) 43 psi (296 kPa) 43 psi (296 kPa)
2nd Reading 19 psi (131 kPa) 17 psi (117 kPa) 18 psi (124 kPa) 21 psi (145 kPa)
Amount Of Drop 24 psi (165 kPa) 26 psi (179 kPa) 25 psi (172 kPa) 22 psi (151 kPa)
Average Range: 22.5-25.5 psi (156-176 kPa) Injector Okay Replace Fuel Injector, Too Much Fuel Pressure Drop Injector Okay Replace Fuel Injector, Too Little Fuel Pressure Drop