Mixture adjustment 3.2

[wrinkledpants]

Is it possible to adjust the mixture on a catless 3.2 with the oxygen sensor? Some say you can only do it with a gas analyzer, and it seems Steve Wong thinks you can do it with a multi-meter and the oxygen sensor. I've got a few issues to clear up before I adjust the mixture again, and would really like to be able to do it myself.

[Hunt3R]

I've talked with Steve about doing this myself because after installing his chip my idle started bouncing on startup. It will bounce a few times and then settle down where it should be and hold that steady for the rest of the drive. Sometimes I have a hard start too, usually it's on "warm-ish" starts. I'll have to crank for ~5 seconds before she starts up. This was actually happening before installing the chip, I assume it's mixture related too and my mixture was always off a little. Steve pointed me to this post where he explained how to test and set the mixture yourself:
Idle Hunting -- The problem continues!!

So the first time I tried this I clamped my multimeter to the male tip on O2 sensor connector coming up into the engine bay from the wheel well, and I put the negative somewhere on the engine and it said I was rich, reading 1.0-1.3, which is what I expected because I could smell how rich she was running and that's why the idle was hunting on startup. So I loosened the mixture screw 1 full turn and it just fell out. Turning it tighter should only richen it further, but I had to do something so I went ahead and screwed it all the way in then backed it out 2 full turns, this is supposed to be the base position. However now I was strangely reading lean, 0.0-0.2. And now no matter where I position the mixture screw I always get a lean reading, sometimes bouncing up to 0.6, but usually around 0.2. If I screw the mixture screw all the way in I can choke the engine it starts running so rich, chokes me too working on it, and it won't want to crank back up, but I will still get a lean reading. And it obvious how it improves as I loosen the screw and lean it out but my reading never changes so I'm just blindly adjusting the mixture and never getting it right. I've even tried spraying carb cleaner into the intake and the idle will rise but my reading still says lean.

I'll go ahead and set the base idle too and drive her for a few days to test it out but I cannot get rid of the idle bouncing on startup, it gets a little better or worse depending on what I do, but I can't find the perfect spot in the dark. Perhaps my multimeter just sucks, I did purchase the cheapest one that Autozone sold and it does seems slow to update sometimes. So if you try it yourself, just be prepared for it to be a PITA.

[ben parrish]

Hunt3R,
Did you have the car warmed up first. The O2 sensor needs to be hot to work properly if I remember correctly?

[Hunt3R]

yup, I take her out for a drive to fully warm up everytime before I attempt this and get at least right on or a little past the 194f mark before coming back to my garage. I replaced my O2 sensor too thinking it was bad. Nothing changed.