Auto ECU's use the sensors to control fuel according to the voltage supplied by them. Most sensors output 1 to 5 volts. More volts is more fuel. The new drive by wire open the throttle according to the throttle position sensor.
That is also trimmed by the traction and ESC controls built into the software.
 The O2 sensors are different in that they only operate on .1 to .9 volts.
They generate this voltage in response to the O2 in the exhaust. The ECM is trying to maintain an A/F ratio of 14.7 to 1. This coincides with a voltage of 0.5. Diagnostics have an output of cross counts which is the number of times per second this voltage crosses the 0.5V's. A high number (cross counts) is desireable for emission controls. As with other sensors, more fuel translates to higher voltage. The ECU then shortens the pulse width, (gives less fuel) to respond to the excess fuel in the exhaust. An O2 sensor that has low cross counts is due to be replaced. Fuel economy will likely be improved. O2 sensors SHOULD not have anything to do with the throttle position stepper motor. As with any man made device, anything can and probably will go wrong.
 A few years ago, Audi had a lot of trouble with the UNINTENDED ACCELERATION PHENOMENOM. One of the car magazines did some reasrch and found the fault to be small close pedals that low time (new owners) mistook the gas pedal for the brake pedal. In each incident the owners were positive they were stepping on the brake. The magazine testers were the same as the new owners that had their car take off. ALL CARS ARE DESIGNED WITH BRAKES THAT CAN HOLD THE CAR BACK.
Modified vehicles MAY be an exception.
 In the expert witness case, the driver could not have had their foot on the brake pedal firmly when they put the vehicle in reverse. If it had been so the vehicle may have moved slightly, but not enough to kill anyone. IMHO.

Dale Davies


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Dale
 I can tell you from experience that the Audi problem was real.  I don't know what the problem was but it wasn't small close peddles.  I had an Audi and experienced an uncommanded acceleration.  Here is what happened.  I turned a corner on a city street and started to accelerate and the car throttle body went "Wide OPEN"  the RPM went to about 6K.  I stood on the brakes and it was still accelerating and about to hit the car in front of me so I kicked the transmission into neutral and without a load the engine RPMs pegged for a split second and then dropped back down to idle.  I parked the car on the side of the road and called the local Audi dealer... Keep in mind it was "Not" under warrantee. They immediately picked it up, gave me a free rental and fixed it for free.  Oh, this was the 4000S model and not the 5000 model car that was suppose to have the "Problem".  I don't know what was wrong with it but I do know it wasn't "peddles"

Mike C.