Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1994 Mazda B2300 SE, AutomaticFACTORY OEM SERVICE PROCEDURE
Fuel Pressure
- Disconnect circuit opening relay. See CIRCUIT OPENING RELAY LOCATIONS table.
- To bleed down fuel in system, start engine (if possible) and allow to die. Connect pressure gauge to fuel line at fuel filter. Reconnect circuit opening relay.
- On B2300, B3000, install EFI Pressure Gauge (T80L-9974-B) to relief valve. Relief valve is located on fuel supply manifold.
- Turn ignition on. Use a jumper wire and connect terminals of Yellow fuel pump check connector together. See FUEL PUMP CHECK CONNECTOR (YELLOW) LOCATION
table. If pump does not run, check fuel pump circuit and circuit opening relay.FUEL PUMP CHECK CONNECTOR (YELLOW) LOCATION
Application Location B2300, B3000 Left Inner Fender Panel, At Rear Of Battery - If possible, start engine. Check fuel pressure with vacuum connected to and disconnected from pressure regulator. See REGULATED FUEL PRESSURE table. 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 ).
- 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 and repair or replace as necessary.
FUEL PUMP PERFORMANCE
| Application | Pressure | ||
|---|---|---|---|
| B2300, B3000 | (1) | ||
|
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REGULATED FUEL PRESSURE
| Application | At Idle W/ Vacuum: psi (kg/cm2 ) | At Idle W/O Vacuum: psi (kg/cm2 ) |
|---|---|---|
| B2300, B3000 | 28-37 (2.0-2.6) | 38-46 (2.7-3.2) |
NOTE:
Fuel pump control unit terminal identification is not available.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.