Part 2 of 3

Chart A-7:

Fuel Line Diagram:

TEST DESCRIPTION: Number(s) below refer to circled number(s) on the diagnostic chart.

1. Fuel pressure below 284 kPa (41 psi) may cause a lean condition and may set a DTC 44. It could also cause hard starting cold and poor driveability. Low enough pressure will cause the engine not to run at all. Restricted flow may allow the engine to run at idle, or low speeds, but may cause a surge and stall when more fuel is required, as when accelerating or driving at high speeds.

2. Restricting the fuel return line causes fuel pressure to build above regulated pressure. With battery voltage applied the pump "test" connector, pressure should rise above 325 kPa (47 psi) as the fuel return hose is pinched.

NOTE: DO NOT allow pressure to exceed 414 kPa (60 psi) as damage to the regulator may result.

3. This test determines if the high fuel pressure is due to a restricted fuel return line or a faulty fuel pressure regulator. High fuel pressure may cause a rich condition and may set a DTC 45.