The 25-year-old German nailed a sensational lap of 1:23.197 in the final 'top-ten shoot-out' section of qualifying, which was more than enough to see him beat Timo Scheider by 0.013 seconds.
"Things couldn"t have gone any better than this," said Tomczyk."After yesterday, we didn"t expect this at all. Even this morning we weren"t really sure whether we"d come up with the right set-up. Everything went perfectly. My thanks to the team.
"We changed something between session two and three again. The team said let's try it – that was the right decision. It was exactly what we were lacking. A big thank you from me to the team. "
Two in a row for Tomczyk
Dane Tom Kristensen made it an all-Audi top-three with Canadian Bruno Spengler the best Mercedes driver in fourth place in his AMG-run machine.
Defending champion Bernd Schneider was fifth quickest in his AMG car with his British team-mate Jamie Green next up.
Another Briton, 21-year-old Paul di Resta, was seventh on the grid in his two-year-old Mercedes run by Persson Motorsport, ahead of ex-Formula One world champion Mika Hakkinen in his AMG car.
Mucke Mercedes driver Daniel la Rosa edged out championship leader Mattias Ekstrom, who could only manage a very disappointing tenth in his Abt Audi, leaving him with a lot of work to do in the race.
British duo Gary Paffett and Susie Stoddart could only manage 11th and 13th for Persson and Mucke Mercedes respectively.