System 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.
Fuel Injector Balance Test Example (Typical)
| Cylinder | 1 | 2 | 3 | 4 |
|---|---|---|---|---|
| 1st Reading | 290 kPa (42 psi) | 290 kPa (42 psi) | 290 kPa (42 psi) | 290 kPa (42 psi) |
| 2nd Reading | 186 kPa (27 psi) | 165 kPa (24 psi) | 179 kPa (26 psi) | 200 kPa (29 psi) |
| Amount of Drop | 103 kPa (15 psi) | 124 kPa (18 psi) | 110 kPa (16 psi) | 90 kPa (13 psi) |
| Average Range: 97-117 kPa (14-17 psi) | Injector OK | Replace fuel injector - too much fuel pressure drop | Injector OK | Replace fuel injector - too little fuel pressure drop |