CIS help?

[Roa, Greg]

>> I also have found that when I set the mixture to where it should be (48%ish), the frequency valve starts >>intermittently buzzing, with the misses corresponding directly with the buzzes.
>
>This kind of sound is usually associated with really low duty cycles - like
>10 to 15 %!

Hummm... interesting.  If that's the case, then I'm probably measuring something wrong, or my meter isn't doing something right.
Should I hear the frequency valve buzzing at all during normal idle?  I was under the assumption that it would be for some reason.

>Measure the O2 sensor voltage with it disconnected from the ECU and
>set the mixture for about 0.5V... then see what the duty cycle is.

Ahhh, good idea.  I hadn't thought to try that.  I'll do that when I get home.  That should give me a halfway decent idea of where the mixture is.

>What kind of meter?

I'm using a craftsman multimeter with duty cycle measurement.  It's this model (if the link will work)
http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=03482022000&tab=specs#tablink

Thanks for the help!

Greg Roa
Cincinnati, OH
86' 4kcsq x2
87' 5kcstq
93' 90CS
83' 944