Fuel Line Pressure/Fuel Pressure Hold Inspection

WARNING: This page is about a different car, the 2002 Mazda B4000, 2002 Mazda B3000, and 2002 Mazda B2300. However, it is still accessible from the selected car via links, so may be relevant.

Check Fuel Pressure

Release fuel pressure. See FUEL PRESSURE RELEASE . Connect scan tool to DLC. Select Active Command Mode. Select Output Test Mode. Press Mode to change to ALL ON mode. Press Start to run fuel pump. Observe fuel pressure. If fuel pressure is 56-72 psi (389-499 kPa), go to step 2 . If fuel pressure is not 56-72 psi (389-499 kPa):
- For zero psi or low pressure, check fuel pump. Repair as necessary. If fuel pump is okay, check fuel line and/or fuel filter for restriction.
- For high fuel pressure, see FUEL PRESSURE REGULATOR under SYSTEM TESTS.

Check Fuel Pressure After One Minute

Observe fuel pressure after one minute. If fuel pressure is within 5 psi (34 kPa) of previous reading, fuel pressure hold is okay. If fuel pressure is not within 5 psi (34 kPa) of previous reading, check for fuel injector leakage. See FUEL INJECTOR INSPECTION under SYSTEM TESTS.