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AFM adjustment



Can anyone offer any seat-of-the-pants guidelines for making sure that an AFM 
is accurately adjusted?  I know that the best way to address this is just 
leave it alone, but unfortunately it's too late for that.  It's also too late to 
mark the wheel before adjustment, because I didn't mark it a year ago when I 
began tinkering around with the fuel/air adjustment, and can't remember where 
it was originally.

I tuned the car originally (on an analyser) with a vacuum line left off, and 
now that I've identified that issue and reattached the line, I'm not sure 
which way to go with the toothed wheel inside the unit to get my ratio back to 
optimum.  I did a few test-and-tune adjustments on a long trip yesterday, but 
could only guage my progress by getting the car back to the fuel consumption 
range in which it used to operate with the previous adjustment.  Right now I have 
it where it gets roughly 29 MPG on the highway, which is roughly where I was 
before attaching the vacuum line.  By going leaner, it would go well beyond 30 
MPG, and seemed to 'like it' (ran well), but I'm not sure that would be good 
for the engine.  So I went a notch in the 'rich' direction from there.

Can anyone offer any general guidelines, starting points, steps to go through 
to guarantee that you have the car in the optimum range?  I would prefer the 
'performance' side of the range, as opposed to the economy/mileage' side.

TIA,
Ken Mitchell
Durham, NC
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