testing oxygen sensors

[smoo]

Is there a resistance value that the O2 sensor should give? Cheers.

[AMB]

I've read that resistance measurement can actually ruin it. Cos it sends a small current into the O2 sensor to measure resistance. You can measure the voltage output when hot and engine running as basic check. But I think its the response/sensitivity that's importnat, cos although it may be giving a correct reading, it may be slow to respond to change.