Idle Stab. system puzzle

[DeWitt Harrison]

Thanks to everyone for all the excellent ideas. All is good now
but I don't exactly know what happened. For a time, I had no
duty cycle signal at the test connector. I eventually got that
back. I did some reseating of connectors as I was doing a
lot of wire continuity checks so maybe I got lucky that way.
Some of the isv problem was due to operator error as I
had the current meter set up incorrectly for a while. Weirdly,
the readings seemed sorta, kinda normal during that period
except a bit to too high and not very adjustable. After I
got those things straightened out, I was finally able to
bring the oxy. duty cycle and isv current into spec. I had
access to a gas analyzer and checked CO and hydrocarbons
were good. I'm impressed by how the oxy. duty cycle plus isv
current tweaking is a very accurate way to set up the
idle mixture as long as the oxygen sensor is good.

I also still don't know why the system behaved so badly initially.
Maybe the bad gas theory is the best one. If that was the issue,
I wonder if putting fresh gas in will mess things up again. I'll
go to the pump as soon as I buy some gas stabilizer.

Thanks again all.

DeWitt Harrison
'88 5kcstq