I've used both the Auto Enginuity and the SGII.
The Auto Enginuity has more direct readings, does bluetooth, and supports both PDA's and PC readouts & logging. The "dongle" that plugs into the ODBII port is about 6" long, so you can't conveniently leave it plugged in for long periods. It will capture & graph O2 sensor readings, timings, Long Term & Short Term fuel trim, MAF flow rates, and lots of other details. No "derived" values. Notably, it does NOT track/log OPEN/CLOSED loop operation, nor system voltage (you can see the current value of either by digging through menus, but they are not tracked/graphed the way the other parameters are).
The SGII is really more of a leave-there-all-the-time monitoring tool. Less details, more "programmable", and very useful. It will display derived MPG & HP values, along with quite a few other ODBII parameters, including OPEN/CLOSED loop status. It's selection of values to display is more limited than the AutoEnginuity.
Hants (KD0CXL) 97 LX450 Slee Armor, 285 BFG/AT, OME 2.5", Altitude Compensator, Kimberley Kamper
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