Two problems related to car throttle stuck have been reported for the 1999 Audi A6. The most recently reported issues are listed below.
The throttle stuck on my '99 Audi A6 2. 8 quattro at 70 mph on interstate I-65 in indianapolis, in. It took both feet on the brake to stop the vehicle and still almost hit someone in the rear (scary). I put the car in park, it red-lined and I turned off the ignition. When I restarted the car the throttle had reset. Fortunately my wife was not driving.
Throttle stuck. It happened during sub zero weather while consumer was driving about 70 mph on a highway. Consumer had to use both feet on the brakes to pull over. When consumer put vehicle in park it red lined. Consumer shut vehicle off , and turned it back on without any problems. Then, dealer looked it over, and said they couldn't find any problems with the vehicle.