Toyota's Alex Wurz recorded the fastest time in Thursday practice ahead of the 2013 World Endurance Championship season finale in Bahrain.
Wurz ended practice one a full 1.425 seconds faster than the quickest Audi, driven by Andre Lotterer.
The #1 Audi had lagged 1.8s off the leader until the final minute of the hour and a half session, when Lotterer improved his time to a 1m44.617s.
The second Joest-run Audi of newly-crowned LMP1 champions Loic Duval, Tom Kristensen and Allan McNish ended the first session in third place ahead of the #8 Toyota, which suffered a problematic start to the weekend.
Anthony Davidson was at the wheel when the car reportedly encountered alternator trouble, which initially restricted his running to one installation lap. The fault kept the car in the pits for over a third of the session.
The Davidson-led crew bounced back to set the pace in the slower second practice.
In the night session it was the turn of the #7 Toyota to hit trouble. Nicolas Lapierre found the gravel at Turn 15 with 36 minutes remaining, bringing out the red flags. Only minor damage was sustained, and he was able to restart and return to the pits during the 10-minute stoppage period.
In GTE, the championship-leading Aston Martin pairing of Darren Turner and Stefan Mucke emerged quickest in practice one, thanks to Turner's time of 1m59.565s.
Richard Lietz and Marc Lieb were quickest in practice two, ahead of the class-leading Aston, although the German pairing's effort of 1m59.730s was 0.2s slower than Turner's benchmark for the day.
The Oak car of Olivier Pla, David Heinemeier Hansson and Alex Brundle had the upper hand in LMP2 during the first session thanks to time of 1m52.389s.
Pecom Racing set the fastest LMP2 time of the day in second practice.
In GTE Am, the all-Danish piloted Aston Martin Vantage V8 of Christoffer Nygaard, Kristian Paulsen and Nicki Thiim led the way in the first session ahead of the #88 Proton Porsche. In practice two, the Matt Griffin/Emmanuel Collard/Francois Perrodo AF Corse Ferrari set the pace.