Test NTC-7A - Checking Oxygen (O2) Sensor Switching
WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, 1995 Dodge Caravan, and 1995 Chrysler Town & Country. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
High fuel pressure may be present in fuel lines. Open fuel system with caution. See FUEL PRESSURE RELEASE
procedure.
- Allow engine to reach normal operating temperature. Using scan tool, read O2 sensor state. If O2 sensor state is switching, system is functioning properly. Test is complete. If O2 sensor state is not switching, check if O2 sensor is locked on lean. If O2 sensor is locked on lean, go to TEST NTC-7B . If O2 sensor is not locked on lean, go to next step.
- Turn engine off. Remove upper half of intake manifold. Turn ignition on. Using scan tool, actuate fuel system. Inspect injectors for fuel leakage. If injectors are leaking, replace leaking injectors or "O" rings as necessary. Perform TEST VER-2.
- If injectors are not leaking, stop fuel system actuation. Turn ignition off. Reinstall upper half of intake manifold. Inspect air cleaner and inlet ducts for restrictions. Repair as required. Perform TEST VER-2. If no restrictions are observed, go to TEST NTC-16A .