Idle and/or 2,500 RPM HC/CO Check

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

1. INITIAL CONDITIONS
- Engine at normal operating temperature
- Air cleaner installed
- All pipes and hoses of air induction system connected
- All accessories switched OFF
- All vacuum hoses for EGR systems, etc. should be properly connected.
- SFI system wiring connectors fully plugged
- Ignition timing check correctly
- Transmission in neutral position
- Tachometer and CO/HC meter calibrated by hand.
2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROX. 180 SECONDS



4. INSERT CO/HC METER TESTING PROBE AT LEAST 40 cm (1.3 ft) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT IDLE AND/OR 2,500 RPM
- Complete the measuring within 3 minutes.
HINT: When performing the 2 mode (2,500 rpm and idle) test, follow the measurement order prescribed by the applicable local regulations.


Troubleshooting
If the CO/HC concentration does not comply with regulations, perform troubleshooting in the order given below.
1. Check oxygen sensor operation.
See oxygen sensor inspection under Computers and Control Systems.
Oxygen Sensor

2. Refer to Diagnosis By Symptom.
Symptom Related Diagnostic Procedures