Pickup 2WD L4-2254cc 2.3L SOHC (4ZD1) MFI (1994)
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Oxygen Sensor: Description and Operation
PURPOSE
The oxygen sensor measures the oxygen content in the exhaust and sends a voltage signal to the Engine Control Module (ECM).
OPERATION
This sensor produces a measureable voltage by comparing the amount of oxygen in the exhaust gas with the amount in the ambient air.
The sensor operates only within a certain temperature range of approx. 285 - 850°C (545 - 1530°F).
The exhaust gases reach the outer surface of the oxygen sensor tip via the openings in the protective sleeve. Ambient air reaches the sensor's inner
surface via channels. The differance in oxygen content produces a voltage read by the ECM.
On some models a heater is provided to allow the sensor to reach operating temperature faster, therefore allowing the ECM to control the A/F
mixture sooner.
