Air/Fuel Mixture: Testing and Inspection
INSPECT CO/HCHINT: This check for determining whether or not the idle CO/HC complies with regulations.
a. Start the engine.
b. Keep the engine speed at 2,500 rpm for approximately 180 seconds.
c. Insert the CO/HC meter testing probe at least 40 cm (1.3 ft.) into the tailpipe during idling.
d. Immediately check CO/HC concentration at idle and/or 2,500 rpm.
HINT:
^ When performing the 2 mode (2,500 rpm and idle) test, follow the measurement order prescribed by the applicable local regulations.
^ If the CO/HC concentration does not comply with regulations, troubleshoot in the order given.
1. Check the A/F sensor and heated oxygen sensor operation.
2. See the table for possible causes, then inspect and correct the applicable causes if necessary.