Hi guys, i receive my new Oxygen Sensor today

but i don't see any difference with the old one!!!!

One question:

Many people are saying that an OS produce voltage when hot and unplug!!!!
Between 0.1 to 1 volt. (rich mixture or poor mixture)!!!!!!!!!!!!!!!!!
For now I don't agree!!!

Should I unplug the battery to reset the ECU?

Explanation: I get the van too normal operating temperature (OS is plug); I
unplug the OS and test voltage to this one (ground the negative and I touch
the OS sender wire with the positive of the voltmeter); I get about 450MV
(it means no reading), I never get .1 to 1 volt. If i touch the van side of
the OS wire only I get a steady .5 Volt when the OS is unplug. When i plug
back the OS (Van running and hot) it get down to 450MV or so but sometime
it give me a brief .7 volt and it goes back very fast to .350MV or no
reading!!!!!. (back and forward) I never get a steady reading; yes my
voltmeter wires are well attached.

What are your suggestions?

Best regards, Ben
http://www3.sympatico.ca/huotx/engine1.htm

Ps: I have 2 new OS sender (error from the company) and the old one, they
all give me the same reading!!! Is my $100 voltmeter faulty!!!!