Hi,
I have a '98 GS300 and has the CEL, VSC and VSC OFF lights come on. Pedal went to the floor, i.e. car went into limp mode (cable throttle only). Switching off the ignition solved the problem for a few miles (warning lights stayed on) Plugged in the OBD2 reader and got the following codes:
P1121 - Throttle position sensor
P1120 - Throttle Pedal Position Sensor
P1128 - Throttle Control Motor Lock
Problem was the Pedal Position Sensor. Turns out the 3 items listed above are closely linked and if one goes faulty, the rest throw up a code. Unfortunately I had already replaced the TPS (bought online for $89) and a 10 minute install. Also had pulled the throttle body out and cleaned it (no harm) - but all of this unnecessary - Pedal Position Sensor was the simple cause.
If I have problems, will post them, but hoping problem solved. Used this forum to figure out the problem - so hopefully this post can help someone else.