Air/Fuel Mixture: Testing and Inspection

INSPECTION

HINT: This check is used only to determine whether or not the idle HC/CO complies with regulations.

1. INITIAL CONDITIONS
a. Engine at normal operating temperature.
b. Air cleaner installed.
c. All pipes and hoses of air induction system connected.
d. All accessories switched OFF.
e. All vacuum lines properly connected.
f. SFI system wiring connectors fully plugged.
g. Ignition timing set correctly.
h. Transmission in neutral range.
i. Tachometer and HC/CO meter calibrated by hand.





2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180 SECONDS
4. INSERT HC/CO METER TESTING PROBE AT LEAST 40 cm (1.3 ft.) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK HC/CO 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.

6. TROUBLESHOOTING
If the HC/CO concentration does not comply with regulations, perform troubleshooting in the order given below.
See the table below for possible causes, and then inspect and correct the applicable causes if necessary.