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Old 05-29-2012, 03:23 PM
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On that EFI system the O2 sensor acts only like a on off switch
Its either in teh low state or the high state.

less than .450MV or more than 450MV. The ECM dos not care otherwise and you cannot trim or bias the O2 sensor voltage up or down.

the computer still looks for the .450MV cossover. If it don;t see it or the sensor response is slow. The ECM just ignores the O2 sensor and reads the tables
AND THROWS A diagnostic code.
Now it will not run in closed loop mode at all.

You cannot tweek the O2

running extended time in limp mode will make the O2 sensor get dirty with carbon and fail.

The whole purpose of the O2 sensor is to allow the ECM (while in Closed loop mode) to maintain a idle and cruise 14.7:1 AFR so the cat converter functions correctly.

The cat converter will soon fail too with extended limp mode driving with a fubared-disabled O2 sensor.

If any of the sensors are reading out of spec to the ECM it will not run in Closed Loop at all.

You sure can sure piss everyone off.
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