flyrotary@lancaironline.net Mailing List Archive

Bill,

Funny you would post this. Last weekend I was attempting auto-tune without much success. I noticed that the O2 bar was off the bottom of the scale. No amount of tweaking of the mixture knob would bring it back. Attempts to auto-tune would result in overly rich mixtures. I had decided that the O2 sensor must have failed, but didn't have time to remove it.

I will take my old one down to Auto Zone and try to match it to another. If it is a narrow-band sensor, it is my understanding that they all work on the same basic principle. So, if it has the proper threads, and a single wire, I don't see why it shouldn't work. That's how I initially picked the one I have been using for the last 200 hours. Anyone see a flaw in my logic?

Mark S.

On Wed, Sep 29, 2010 at 8:10 AM, Bill Schertz <wschertz@comcast.net> wrote:

Was going to do some auto tune in the air yesterday, to get to some regions of the performance map that can't be reached on the ground.

Took off and the O2 sensor indication completely disappeared from the EM-2 display. Did one circuit of the airport and landed.

Discovered that the O2 sensor had failed (physically -- the top fell off and separated from the body). This caused me to raise the following questions.

1. I believe that the oxygen sensor readout is only that, not used by the EC-2 for control purposes.

2. When in auto tune, is the EM-2 looking at the sensor for indications of which way to adjust the mixture? If not, what is the feedback mechanism?

I went to the Auto parts store for a replacement, and ran into the problem that there are 100's of different oxygen sensors, and they need to know what car it came from. Anyone have the specs on what this sensor is?

Bill Schertz
KIS Cruiser #4045
N343BS
Phase I testing