Inspecting Fuel System
WARNING:
High fuel pressure may be present in fuel lines. Open fuel system with caution. See FUEL PRESSURE RELEASE procedure.
- Ensure throttle cables are not holding throttle open. If throttle is held open, repair as required. Perform TEST VER-1. If throttle is not held open, using scan tool, read Throttle Position Sensor (TPS) voltage.
- If voltage is less than 1.5 volts, go to next step. If voltage is more than 1.5 volts, disconnect TPS connector. Inspect terminals. Repair as required. Perform TEST VER-1. If terminals are okay, replace TPS. Perform TEST VER-1.
- If vehicle is not equipped with a factory vehicle theft alarm, go to next step. If vehicle is equipped with a factory vehicle theft alarm, using scan tool, read theft alarm status. If scan tool displays FUEL ON, go to next step. If scan tool does not display FUEL ON, see TESTS W/CODES - BODY CONTROL COMPUTER article in ENGINE PERFORMANCE.
- Using scan tool, actuate fuel system. Listen for fuel pump operation at fuel tank. If fuel pump operation cannot be heard, go to TEST NS-5A. If fuel pump operation can be heard, turn ignition off.
- Ensure fuel tank is at least 1/4 full. Release fuel pressure. Install a fuel pressure gauge in fuel supply line. Turn ignition on. Using scan tool, actuate fuel system. Observe fuel pressure gauge. See FUEL PRESSURE SPECIFICATIONS table.FUEL PRESSURE SPECIFICATIONS
Application psi (kg/cm2 ) Passenger Car Without Flexible Fuel 34-44 (2.4-3.1) - If fuel pressure is more than specification, go to TEST NS-4B. If fuel pressure is less than specification, go to TEST NS-4A. If fuel pressure is within specification, go to next step.
- Check fuel injector area for fuel flow. If fuel is flowing, go to TEST NS-4C. If fuel is not flowing, go to next step.
- If vehicle initially started and stalled repeatedly, go to TEST NS-7A. If vehicle did not initially start and stall repeatedly, go to TEST NS-3A.