At 10:01 PM 2/3/2001, Tom Young wrote:
>I'm not sure this is correct.  Doesn't "open loop" mean the ECU isn't
>receiving a signal from the O2 sensor, and operating in its "default"
>mode?  Once the O2 sensor is sending a signal, the ECU goes into
>"closed loop" mode, meaning it's using the voltage generated by the
>sensor, which is in turn affecting the sensor's voltage.

True -- but he's talking about *disconnecting* the lambda sensor from the
ECU and measuring its output voltage directly with a high-impedance
voltmeter.  The ECU notices that the lambda signal has gotten stuck between
too rich and too lean, and ignores it, i.e. goes to open-loop mode.

david

David Beierl - Providence, RI
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