Part 2 of 3

Chart A-7:

Fuel Flow Circuit:

TEST DESCRIPTION: The numbers below refer to circled numbers on the diagnostic chart.

1. Pressure below 284 kPa (41 psi) may cause a lean condition and may set a Code 44 or Code 32. 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 flow at the fuel pressure gauge (at "B") causes fuel pressure to build above regulated pressure. With battery voltage applied to the pump test terminal, pressure should rise above 325 kPa (47 psi) as the gauge outlet hose is restricted.

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.