Duty cycle 90.5% means ??????

[richard28]

On my 87 300e, I got a duty cycle reading with key on , engine off, of 90.5%, no fluctuations. Is this the same as a dead O2 sensor, or does it mean something else. I have a new sensor & could test it easily but only at the front pass seat-- I myself can't get under the car (the PO lowered it 2 inches). Thanks, esp to Stevebr if you can help me out.

Rich