i've looked at a couple of oxygen-sensor-based A/F meters, been in contact with a couple of the technical guys at the more promising candidates. i asked each of them "since my injection specs are in %CO, how do i correlate that to A/F"

one guy wrote back "i have no idea, go research the Internet" (not quite confidence-inspiring...) and the other guy said "we get asked this a lot, and there are several factors, we should put a technical paper on the website." (IOW - they don't know either, but they at least understand it's not a trivial issue or a stupid question ...)

my car has been acting up A LOT and i got tired of chasing my tail and Monday-morning no-start, in addition to the bad running, intersection-stalling, etc... checked around, bit the bullet on a CO meter. this one : Affordabl;e CO Meter Be advised there's a 'pricing special' i forgot to reference in my initial order, too soon to tell if i get credit for it with my followup email ..

it hasn't come yet so i can't comment on the timliness of delivery, quality of the unit, or accuracy of the measurement. and anyway, i'll have to get the car started before it'll tell me squat, although my sooty-black fuel-wet spark plugs are a pretty good clue -something- is unhappy ...

i'll post follow up information as i get it ...