NHTSA Complaint #11424539 — 2000 TOYOTA SIENNA

I have a 2000 Sienna with 305000 miles. I have never had trouble with this vehicle until about 2 weeks ago. When I am stopped and my car is in drive, I just tap the gas pedal for a second and the engine RPM will increase to about 2000 RPM and will stay there until I put the car in neutral or turn the engine off. This is a problem because my breaks barely hold this and I must put the car into neutral for the car to stop pulling forward. Putting the car into neutral resets the rpm. If there is no car in front of me, I can release the brakes and the vehicle will continue to accelerate until the transmission switches to second gear, at this point I can drive normally. One time the vehicle continued to accelerate even after switching gears, I put the vehicle into neutral and the engine went to over 4000 RPM, the brakes could not stop the vehicle, I had to turn the engine off. The gas pedal is not sticky or stuck, floor mats are not in the vehicle. I can rev the engine normally when I am in park, this only happens when I am in gear. I have checked the Throttle Body, Throttle Position Sensor and disabled the cruise control module, I can see no reason for this to happen. I have seen many complaints about this same issue online but have not found a resolution. I can buy an ECM but this is an expensive trial. I will take it to the dealer from here.