I was asked to post a "How To" on proper Fuel Pressure Testing in the Protege. This Test Procedure Includes all Mazda Protege & Protege5 , Also Includes Mazda Miata, Millenia(2.3L,2.5L), 626(2.3L,2.5L), (Does NOT Include B2300, B3000, B4000 & Tribute)
Disclaimer:WARNING!!! Use this procedure at your own risk. Gasoline/Fuel is a volatile, combustible liquid and if handled incorrectly can be dangerous! CAUTION!!! Improper handling of fuels can lead to serious injury and/or death. I am in no way responsible for any thing that happens to you at all...ever.
1. Disconnect negative battery cable. Release Fuel Pressure.[To release fuel pressure: Remove fuel filler cap to release tank pressure. Disconnect Fuel Pump Relay. (Fuel Pump Relay located Fuse/Relay Box on Left Side of Engine compartment.) Start Engine(if possible) and allow to die. Crank engine several times. Turn Ignition Switch off. Reconnect Fuel Pump Relay.] Install fuel pressure gauge in fuel supply line.(The Fuel Test Gauge I own came with various sizes of "T" fittings & clamps to easily and securely install the gauge "in-line" with fuel supply, If the gauge you're using doesn't have them then you will need to purchase the correct size T-fitting and clamps to securely install test gauge in line with fuel supply,(these can generally be found at a competent auto parts supplier). If it leaks then your pressure reading will be inaccurate & not to mention, leaking fuel can be dangerous.) Reconnect negative battery cable. On all models except 626, Reconnect negative battery cable and proceed to next step. On 626, go to step 3.
2. Locate DLC-1 under hood. Connect a fused jumper wire between DLC-1 terminals F/P and GND. See Figure. Turn ignition switch on and observe fuel line pressure.(Fuel Line Pressure on Protege & Protege5 should be between 39-45 psi(2.7-3.2kg/cm2).
3. Locate and remove fuel pump relay. Connect fused jumper wire between ground and fuel pump relay socket terminal No. 30. Reconnect negative battery terminal to operate fuel pump. Observe fuel line pressure. 626 line pressure; 2.0L: 37-46psi(2.6-3.3kg/cm2), 2.5L: 39-45psi(2.7-3.2kg/cm2)
Identifying DLC-1 Terminals:
Disclaimer:WARNING!!! Use this procedure at your own risk. Gasoline/Fuel is a volatile, combustible liquid and if handled incorrectly can be dangerous! CAUTION!!! Improper handling of fuels can lead to serious injury and/or death. I am in no way responsible for any thing that happens to you at all...ever.
1. Disconnect negative battery cable. Release Fuel Pressure.[To release fuel pressure: Remove fuel filler cap to release tank pressure. Disconnect Fuel Pump Relay. (Fuel Pump Relay located Fuse/Relay Box on Left Side of Engine compartment.) Start Engine(if possible) and allow to die. Crank engine several times. Turn Ignition Switch off. Reconnect Fuel Pump Relay.] Install fuel pressure gauge in fuel supply line.(The Fuel Test Gauge I own came with various sizes of "T" fittings & clamps to easily and securely install the gauge "in-line" with fuel supply, If the gauge you're using doesn't have them then you will need to purchase the correct size T-fitting and clamps to securely install test gauge in line with fuel supply,(these can generally be found at a competent auto parts supplier). If it leaks then your pressure reading will be inaccurate & not to mention, leaking fuel can be dangerous.) Reconnect negative battery cable. On all models except 626, Reconnect negative battery cable and proceed to next step. On 626, go to step 3.
2. Locate DLC-1 under hood. Connect a fused jumper wire between DLC-1 terminals F/P and GND. See Figure. Turn ignition switch on and observe fuel line pressure.(Fuel Line Pressure on Protege & Protege5 should be between 39-45 psi(2.7-3.2kg/cm2).
3. Locate and remove fuel pump relay. Connect fused jumper wire between ground and fuel pump relay socket terminal No. 30. Reconnect negative battery terminal to operate fuel pump. Observe fuel line pressure. 626 line pressure; 2.0L: 37-46psi(2.6-3.3kg/cm2), 2.5L: 39-45psi(2.7-3.2kg/cm2)
Identifying DLC-1 Terminals:
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