Test NTC-7A - Checking O2S Switching
WARNING:
High fuel pressure may be present in fuel lines. Open fuel system with caution. See FUEL PRESSURE RELEASE
procedure in this article.
- Allow engine to reach normal operating temperature. Using scan tool, read O2S state. If O2S state is switching, system is functioning properly. Test is complete. If O2S state is not switching, check if O2S is locked on lean. If the O2S is locked on lean, go to TEST NTC-7B . If O2S is not locked on lean, turn engine off.
- Release fuel pressure. Install a fuel pressure gauge in fuel supply line. Turn ignition on. Using scan tool, actuate fuel system. Allow fuel pressure to stabilize. Stop fuel system actuation. Monitor fuel gauge for one minute. If fuel pressure drops more than 10 psi (.7 kg/cm2 ), replace leaking injector(s) or "O" ring(s) as necessary. Perform TEST VER-2 .
- If fuel pressure does not drop more than 10 psi (.7 kg/cm2 ), inspect air filter and air inlet ducts for restrictions. Clean restricted air inlet system as necessary. Perform TEST VER-2 . If no restrictions exist, go to TEST NTC-16A .