Fuel Pressure (B2300, B3000 & B4000)
WARNING: This page is about a different car, the 1995 Mazda B4000, 1995 Mazda B3000, and 1995 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.
- To bleed down fuel in system, install Fuel Pressure Gauge (49 UN01 010) to Schrader valve. Schrader valve is located on fuel supply manifold. Place drain hose in suitable container and press pressure relief button. If 49 UN01 010 is not available, disconnect inertia fuel shutoff switch and crank engine 15-20 seconds to relieve pressure. Connect pressure gauge to fuel line at fuel filter. Reconnect inertia fuel shutoff switch.
- Connect New Generation Star (NGS) Scan Tester (49 T088 0A0) to Data Link Connector-2 (DLC-2). DLC-2 is located under left side of dash, near steering column. Select ACTIVATE COMMAND MODE. Select FUEL PUMP RELAY control. Turn relay on. If pump does not run, check fuel pump circuit and fuel pump relay. See FUEL PUMP CIRCUIT & RELAY (B2300, B3000 & B4000).
- Start engine. Check fuel pressure with vacuum connected to and disconnected from pressure regulator. See REGULATED FUEL PRESSURE table. Turn engine off. Turn on fuel pump relay for 30 seconds. Note fuel pressure. Turn relay off. Wait one minute and ensure residual pressure is within 5 psi (.35 kg/cm2 ) of maximum pressure reading.
- Turn ignition off and disconnect scan tester. If pump does not meet specifications, check fuel pump circuits, fuel pump, fuel tank and fuel filter. Repair or replace as necessary.
FUEL PUMP MAXIMUM PRESSURE
| Application | Pressure | ||
|---|---|---|---|
| B2300, B3000 & B4000 | (1) | ||
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REGULATED FUEL PRESSURE
| Model | @ Idle W/Vacuum psi (kg/cm2 ) | @ Idle W/O Vacuum psi (kg/cm2 ) |
|---|---|---|
| B2300, B3000 & B4000 | 35-40 (2.5-2.8) | 35-45 (2.5-3.2) |