I finally got the WBO2 sensor installed. I previously set the idle screws at best vacuum at idle.
The youtube video (
click here) shows some interesting results. The video has four snippets.
First section is cold start - cold idle - i have to hold the pedal for a few seconds at 2000 rpm or so until it warms up enough to run.
Second section is about 20 seconds at steady cruise. Third section is hot idle waiting at a light. Fourth is the two WOT pulls in second gear. There was a bit of traffic this morning, so I couldn't stay in it very long. The last few seconds of the clip you can see it starts to break up at around 4500 rpm.
Some observations:
Cold and hot idle is very rich. 11:1 or so. This surprised me since I had set the idle screws to best vacuum on a hot motor.
Cruise is about 11.5:1 - this is because I am basically running on the idle circuit, maybe a little of the transition circuit. Since the idle circuit is so rich, cruising around 1500 rpms would be too.
It is hard to read the meter at WOT with all the shaking and the video frames fighting, but it looks like WOT is around 12.5-13. This seems fine. It doesn't seem to go dead lean as would be expected with it mis-firing.
When I got home, I adjusted the idle mixture screws. It was very sensitive to even slight changes. Screwing in the screws even 1/16th of a turn resulted in about 0.5 to 1.0 change on the gauge. I didn't know the idle mixture screws were so sensitive - plus, it dropped my intake vacuum from 14 to 13 inHg going from 11:1 to 13.5:1. I also had to increase my idle screw a touch to reset the idle back to 1000 rpm as it this change dropped my rpms about 75-100 rpms.
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