Today I was driving my A4 1.8 T Audi. I noticed an EPC light flicking on and off. I thought it was going to go away. I then got to stop to drop off something. Thereafter, the car would start and cut off after trying to engage the drive mode. I tried disconnecting the battery. It did not work. I then waited for some time and it started well. I went home nicely. What could be the reason for this? Can I safely say the error has cleared up?

 

Check for codes but mine did exactly this and it was a easy to replace Crankshaft sensor @ US $50.
When it gets hot it breaks contact inside the sensor & you cannot restart the engine untill it's cold again.
Once it's cold again, it will start up and drive & then when it gets hot, breaks contact & runs badly & mine threw up a light on the dashboard & once the car was turned off it wouldn't start untill it was cold again.

As soon as I figured it out via a cheap OBDII, I stopped using it untill the part arrived & a hour later was driving it again.
Youtube it.
Oh, to check it you can unplug it & check its resistance at the plug. Mine broke contact at 50°C I think.