Fuel Pressure Test
- Disconnect negative battery cable. Release fuel pressure. See FUEL PRESSURE RELEASE
under FUEL SYSTEM.CAUTION: Cover fuel plate with shop towel when removing, as some fuel pressure may exist in fuel rail.
- Remove bolts and fuel plate from end of fuel rail. Fuel plate is located on driver's side of front (radiator side) fuel rail. See Fig 1 . Fuel plate is near the air intake hose.
- Install Hose Adapter (MD998742), Adapter Hose (MD998709) and fuel pressure gauge on end of fuel rail. See Fig 1 . Connect scan tool to Data Link Connector (DLC), located below driver's side of instrument panel. See Fig 2 .
- Turn ignition on. Using scan tool, actuate ASD fuel system test to activate fuel pump and pressurize fuel system. Note fuel pressure. Fuel pressure should be within specification. See the FUEL PRESSURE SPECIFICATIONS
table. If no fuel pressure exists, fuel pump relay and control circuit may be defective. See FUEL PUMP RELAY
under FUEL SYSTEM. If fuel pressure is correct, go to step 9).FUEL PRESSURE SPECIFICATIONS
Application psi (kg/cm2 ) Avenger & Sebring (1) 47-50 (3.3-3.5) (1) Manufacturer lists fuel pressure with engine off, ignition on and using scan tool to activate fuel pump. - If fuel pressure exceeds specification, go to step 8). If fuel pressure is less than specified, check for clogged fuel filter. Fuel filter is located on frame rail, near fuel tank. Replace fuel filter if clogged, and recheck fuel pressure. If fuel pressure is now okay, go to step 9). If fuel pressure is still not within specification, go to next step.
- Check for fuel pressure in fuel return hose at fuel pressure regulator. Fuel pressure regulator is installed at "T" fitting at end of fuel filter, located on frame rail, near fuel tank.
- If fuel pressure exists in fuel return hose, fuel pressure regulator is leaking. If no fuel pressure exists in fuel return hose, low fuel pressure is caused by defective fuel pump. Fuel pump is located in fuel tank. Replace components as necessary. See the REMOVE/INSTALL/OVERHAUL article.
- If fuel pressure exceeds specification, check for restricted fuel return hose or pipe. If fuel return hose or pipe are not restricted, check for a binding valve in the fuel pressure regulator. Fuel pressure regulator is installed at "T" fitting at end of fuel filter, located on the frame rail, near fuel tank. See the REMOVE/INSTALL/OVERHAUL article. Once correct fuel pressure is obtained, go to next step.
- With scan tool actuated and fuel pressure obtained, turn ignition off and note fuel pressure. Fuel pressure should not decrease within 2 minutes.
- If fuel pressure decreases gradually after ignition turned off, check for leaky fuel injector/leaky valve in fuel pressure regulator. Fuel pressure regulator is installed at "T" fitting at end of fuel filter, located on frame rail, near fuel tank. Replace components as necessary. See the REMOVE/INSTALL/OVERHAUL article. Go to step 12).
- If fuel pressure decreases immediately after ignition is turned off, check valve in fuel pump is held open. Replace fuel pump, located in fuel tank. See the REMOVE/INSTALL/OVERHAUL article. Go to step 12).
- Ensure ignition is off. Remove scan tool. Release fuel pressure. Remove fuel pressure gauge. Reinstall fuel plate.