Can you do the AFC hack with the OBD2 ecu?? And if so will it be as effective or will it just throw codes at you..

 

It will work, but you have to add just a little more gas over OBD1, because the secondary oxygen sensor will cause slightly leaner (then what you tuned for) readings. I dont know by how much, but I know that the secondary oxygen sensor is about 1/4 of the actual air/fuel mixture caliberation in the ECU (the rest is MAP, IAT, TPS, etc...)

But yes, it will work - just may take more tuning to get it right.

 

WOT throttle aka open loop rely entirely on preset fuel and ignition maps. The O2 "interference" is at part throttle cruise for fuel efficiency.

It's no harder to tune than OBD1, OBD0, or a Volvo 240T station wagon.