Fuel Pump Pressure Test
NOTE:
If scan tool is not available use following procedure to operate fuel pump On. Remove fuel pump relay from underhood fuse/relay box. Using fused jumper, jumper fuel pump relay socket cavities No. 1 and 5. See Fig 1
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- Turn ignition off. Ensure A/C is off (if equipped). Release fuel system pressure. See FUEL SYSTEM PRESSURE RELEASE . Install Fuel Pressure Gauge Set (J-34730-1) or equivalent to fuel rail or fuel supply line. Install fuel pump relay. Connect Tech 2 or equivalent scan tool to Data Link Connector (DLC). DLC is located under small cover on left side of dash. Turn ignition on. Using scan tool, command fuel pump On. Observe fuel pressure gauge. Fuel pressure on all models should be 42-55 psi (290-376 kPa). If fuel pressure is not as specified, see appropriate FUEL SYSTEM DIAGNOSIS procedure. If fuel pressure is as specified, testing is complete.
- Start engine let fuel pressure build to maximum pressure. Observe fuel pressure gauge. When engine is running, fuel system pressure should drop 3-15 psi (21-105 kPa) from engine off fuel pump running specification. If pressure does not drop as specified, see appropriate FUEL SYSTEM DIAGNOSIS procedure. If fuel pressure drops as specified, testing is complete.