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Fuel Pressure

  1. On all 4-Cyl moddels, disconnect circuit opening relay (located behind left kick panel on B2600i and 323, on panel near clutch pedal on MX-6 and 626). On MPV, relay is mounted on ECU. ECU is under protective cover on passenger side floor. Start engine (if possible) and allow to die. Connect pressure gauge to fuel line at fuel filter.
  2. Turn ignition on. Using a jumper wire, connect terminals of Yellow fuel pump check connector together. Fuel pump check connector is located on firewall, near windshield wiper motor on B2600i, MX-6, 323 and 626, and near airflow sensor on MPV. If pump runs, check fuel pump circuit and circuit opening relay.
  3. If possible, start engine. Check fuel pressure with vacuum connected to and disconnected from pressure regulator. Turn engine off and disconnect jumper wire at fuel pump check connector. Wait 10 minutes and ensure residual pressure is at least 21 psi (1.5 kg/cm2 ).
  4. Operate fuel pump by jumpering fuel pump test connector. Check fuel pump performance. Pinch hose between pressure gauge and fuel filter. Do not hold longer than necessary to check pressure. See FUEL PUMP PERFORMANCE table. If pump does not meet specifications, check fuel pump circuits, fuel pump, fuel tank, fuel filter or replace fuel pump.
FUEL PUMP PERFORMANCE

Application Pressure psi (kg/cm2 ) Min. Vol. in 30 sec. Pts. (L)
B2600i, MPV, MX-6 (1) , 323 (2) , 626 (1) 64-85 (4.5-6.0) 1.1 (.66)
(1) 5.7 psi (9.4 kg/cm2 ) on transfer pump.
(2) No info. available for 323 4WD transfer pump.
REGULATED FUEL PRESSURE - AT IDLE

Application w/Vacuum psi (kg/cm2 ) w/o Vacuum psi (kg/cm2 )
B2600i, MPV & 31-38 (2.2-2.7) 38-46 (2.7-3.2)
MX-6 & 626 27-33 (1.9-2.3) 34-40 (2.4-2.8)
323 26-31 (1.8-2.2) 34-40 (2.4-2.8)