Fuel Pressure
WARNING:
ALWAYS relieve fuel pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components. See FUEL PRESSURE RELEASE.
NOTE:
For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS
article.
- Release fuel pressure. See FUEL PRESSURE RELEASE. Install fuel pressure gauge. Connect a jumper wire between fuel pump test terminal at the Data Link Connector (DLC) and ground. See Fig 1 Turn ignition on, but DO NOT start engine. This activates the fuel pump.
- Measure and record Key On, Engine Off (KOEO) fuel pressure. Start engine. Measure and record Key On, Engine Running (KOER) fuel pressure. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS article. Turn ignition off and monitor fuel pressure for one minute. Fuel pressure should not drop more than 5 psi (34 kPa).
- If fuel pressure is within specification, test is complete. If fuel pressure is not within specification, check fuel filter and lines for restriction(s). Repair or replace as necessary. If fuel pressure is still not within specification, install fuel pressure gauge (if removed).CAUTION: Inspect fuel system for leaks or damage before testing fuel pump.
- Start engine and observe fuel pressure gauge. Gently squeeze fuel return hose. If fuel pressure increases while squeezing fuel return hose, replace fuel pressure regulator. If fuel pressure does not change while squeezing fuel return hose, check for plugged fuel inlet strainer or defective fuel pump. Repair as necessary.
NOTE:
For additional fuel system testing information, see the SYSTEM/COMPONENT TESTS - EEC (2.5L)
article.