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Home >> Toyota >> 1997 >> RAV4 2-Door 2WD L4-2.0L (3S-FE) >> Repair and Diagnosis >> Powertrain Management >> Emission Control Systems >> Testing and Inspection >> CO/HC Check
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CO/HC Check

IDLE AND/OR 2,500 RPM CO/HC CHECK

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

1. Initial conditions.
(a) Engine coolant 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) Sequential Multiport Fuel Injection (SFI) system wiring connectors fully plugged.
(g) Ignition timing set correctly.
(h) Transmission in neutral position.
(i) 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 concentrations at idle and/or 2,500 RPM.
Complete the measuring within 3 minutes.

NOTE: When doing 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.
(a) Check oxygen sensor operation.





(b) See the table for possible causes, then inspect and correct the applicable causes if necessary.









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