Fuel Pump Pressure Inspection (Protege & Protege5)
- Disconnect negative battery cable. Disconnect quick release fuel line connector from fuel rail (near pulsation damper). Refer to FUEL LINE CONNECTORS (MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5
under FUEL SYSTEM in REMOVAL, OVERHAUL & INSTALLATION article. Install Fuel Pressure Gauge (49-N013-1A0C) onto main fuel line until click is heard. Pull quick release connector by hand and ensure fuel line is installed securely. Turn lever on fuel pressure gauge as shown in Figure. Go to next step.
- Reconnect negative battery cable. Connect a fused jumper wire between DLC-1 F/P terminal and body ground. See Figure. Turn ignition on to operate fuel pump and observe fuel pressure. For fuel pressure specifications, see FUEL SYSTEM
in SERVICE & ADJUSTMENT SPECIFICATIONS article. If fuel pressure is not as specified, turn ignition off and check following:
- Fuel pump relay.
- Fuel filters (low and high pressure) for clogging.
- Fuel line for restriction or leakage.
If problem is found, repair as necessary. After repair, go to step 4. If no problem is found, go to next step.
- Turn ignition on for 10 seconds to operate fuel pump. Turn ignition off. Wait 5 minutes and observe fuel pressure. See FUEL PUMP HOLD PRESSURE SPECIFICATIONS table. If fuel pump hold pressure is not as specified, perform fuel pressure regulator and fuel injector inspection. Refer to FUEL PRESSURE REGULATOR INSPECTION or FUEL CONTROL
under FUEL SYSTEM in SYSTEM & COMPONENT TESTING - MAZDA6, MIATA, MPV, PROTEGE & PROTEGE5 article. If no problem is found, replace fuel pump. After repair, go to next step.
- Disconnect fused jumper wire. Disconnect fuel pressure gauge and reconnect fuel line to fuel rail. Pull quick release connector by hand and ensure fuel line is installed securely. Complete AFTER REPAIR PROCEDURE .