There is something about that: you can't measure the output of an O2 or
Lambda sensor with a standard DVM.

I have also heard that you can damage one trying to measure it with a
DVM. I don't know if I buy this, except maybe if the loading during the
warmup stage screws it up. Far fetched I think.

I do know this, you don't really get any kind of meaningful reading on
a DVM from an O2 sensor.

JURB