Q: I have a 2001 Audi a6 Quattro Biturbo that got too hott driving and turned off now it wont turn back on

The status of the oxygen sensors is unrelated to the present no start. Overheating has the potential to cause head gasket leaks and valve and piston damage. You should measure cylinder compression to rule out low compression as a cause of the no start condition. If cylinder compression is normal, it is possible that the high heat has damaged one or more control components. For example, high heat can damage the crankshaft position sensor but there are many other components that could plausibly account for the trouble. Again, due to the overheating, I would first check the engine compression and then you have to run down all the usual fuel, ignition, and air induction system faults that could account for a no start condition. The high heat could have even warped the intake manifold causing a substantial vacuum leak. Overheating has the potential to damage the engine cooling system thermostat, too, so, in the course of any repair that is performed be sure to replace the thermostat. If you want the no start condition (as well as the overheating) diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a no start diagnostic and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.