Wanted to get any opinions from folks who may have a lot more experience than me on this.
A couple of years ago I bought an older A/F Monitor to help me play with the Mach1 carb tuning- as an amateur! It is one of those that you insert in the exhaust and so I assume it has an oxy sensor in the pipe as there are wires coming out to the unit. It is pretty old and I can find no instructions online and cannot find any info on it.
So, when inserted in the mustang it reads extremely rich almost all the time, backs off a bit towards a leaner reading but bounces around all over the place and is really of no use due to the instability of the reading. Took it for a drive with the unit strapped in and it offer no additional useful info, bounced around and was not giving logical readings to acceleration and decel.
So we have tried it on a coupe of more modern injected cars and it reads very much stable and approximately where I would expect, 14.7 ish on one and a bit more lean on another. Richer while choke engaged then leaner. Did not do a driving test but idling seemed to be reasonably stable and probably fairly accurate.
Put it on brothers 352 Galaxie and same result as the mustang- all over the place and very rich.
So, are our carb vehicles very rich compared to modern ones, do they spit out rich fumes then more lean ones ?
Am I doing something fundamentally wrong in the way I have plugged it in? Or are specific testers needed for our cars?
Am I wasting my time and hence the unit goes to the bin? (this is my current thinking!)
