1A
Idle Mixture Inspection / Adjustment (Vehicle without Heated Oxygen Sensor)
All vehicles not equipped with heated oxygen sensor are shipped with their CO% factory adjusted as follows.
Engine idle mixture (CO%)
0.5 – 1.5% at specified idle speed
Idle mixture adjustment should never be changed from the original factory setting. However, if during diagnosis, the check indicates idle mixture to be the cause of a driver performance complaint or emission failure, the idle mixture can be adjusted using the following procedures.
NOTE:
For this inspection and adjustment, exhaust gas tester (CO meter) and engine tachometer are necessary.
1) Check idle speed according to Idle Speed / Idle Air Control (IAC) Duty Inspection:M13A without VVT .
2) Using exhaust gas tester, check that idle mixture CO% is within above specification. If it is out of specification, adjust it to specification by turning resistor knob.
NOTE:
CO adjusting resistor knob to “A” increases CO% (A/F mixture becomes rich) and turning it to “B” decreases CO% (A/F mixture becomes lean).
1. CO adjusting resistor
3) If idle mixture has been adjusted, confirm that idle speed is within specification.