It has been mentioned in other threads that the RENIX version how o2 content is measured is a little different than you would expect. It is pretty confusing and totally counter-intuitive.
From the RENIX manual
"When the oxygen content is low, (rich mixture), the voltage signal will be less than 2.5 volts. A lean mixture (high oxygen content) the voltage is signal is above 2.5 volts."
So
1 volt = rich
5 volts = lean
2.5 just right....
(more o2= lean mixture = lower resistance = higher voltage ???)
From wikipedia which quotes other references so it must be true. :sunshine:
"So, for fuel-rich exhaust (lower oxygen concentration) the resistance is low, and for fuel-lean exhaust (higher oxygen concentration) the resistance is high."
(more o2= lean mixture = higher resistance = lower voltage )
Another reference
http://www.hybridconversions.com/v/vspfiles/assets/images/oxygen sensors explained.pdf
As titania is an N-type semiconductor with a structure TiO2-x, the x defects in the crystal lattice conduct the charge. So, for fuel-rich exhaust the resistance is low, and for fuel-lean exhaust the resistance is high.
(more o2= lean mixture = more resistance = lower voltage) same language that wikipedia uses)
(more o2= lean mixture = higher resistance = lower voltage )
Anyway I spent some time on this today and I think I can confirm that the RENIX ECU will see high voltage as rich and low as lean. I had a bad fuel pressure regulator and it caused the o2 sensor to read less than 1 volt consistently at idle. This drove me crazy and I am hoping this research helps others that are struggling with the same troubleshooting dilemma. If you have a RENIX sensor that consistently reads less than 1 v after warmup something is causing it to run rich and it is likely to be the fuel pressure regulator. It means the o2 sensor is functioning properly.
Think that this is confusing because you have multiple reverse logic things happening.
Higher resistance = lower voltage higher o2= less resistance = higher voltage... arghh!!!
So I smelled a rat and decided to read the bloody patent. Which I have linked to and list the relevant excerpt below. It would appear that Titania sensor's resistance actually decreases with the amount of o2 in the stream. It is an inverse relationship....
(more o2= lean mixture = lower resistance = higher voltage )
I am going to challenge Wikipedia on this unless anyone sees what I am sure I am missing. :bs:
http://www.google.com/patents?id=pF...AA#v=onepage&q=Patent number: 5111792&f=false
!!!1 Done.