Fuel Line Pressure/Fuel Pressure Hold Inspection
- Check Fuel Pressure -
Release fuel pressure. See FUEL PRESSURE RELEASE
under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Install Fuel Pressure Gauge (49-UN01-010). Turn ignition on, engine off. 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. Turn relay off with scan tool. If fuel pressure reading was 30-65 psi (207-448 kPa), go to step 2
. If fuel pressure reading was not 30-65 psi (207-448 kPa):
- For zero psi or low pressure, check fuel pump. If fuel pump is okay, check fuel line and/or fuel filter for restriction. Repair as necessary.
- For high fuel pressure, go to next step.
- Check Fuel Pressure After One Minute -
Observe fuel pressure after one minute. If fuel pressure reading is within 5 psi (34 kPa) of previous reading, fuel pressure hold is okay. If fuel pressure reading is not within 5 psi (34 kPa) of previous reading, check for fuel injector leakage. See FUEL INJECTOR INSPECTION
testing under SYSTEM TESTS.