1991 240sx: How to voltage test O2 sensor ?

[vancouverbc]

I get over 1 volt when rpm's are below 2000 and around .998 when rpm's over 2000.

1 volt is rich and zero volts in lean.

I guess I am supposed to create a rich and lean condition and see if o2 sensor detects this.

[dkdeleon68]

[vancouverbc]

http://www.fileden.com/files/2...r.doc

Thanks. Ive been told that the self-diagnostic test is not definitive. I get a normal result from self-diagnostics mode 2 O2 sensor test.