Senna hits trouble as Pantano flies

Bruno Senna faces an uphill battle to close the seven-point gap to GP2 Series points leader Giorgio Pantano after suffering a throttle problem during free practice in Valencia that rendered him 18th fastest, 1.8s behind the Italian.

With just 30 minutes to learn the new Spanish street circuit, Senna was waiting in a line of cars ready to go on-track when he was pushed to the side and lost 10 minutes while his iSport team went to work on the problem.

"The throttle would not go back to zero percent," said Senna. "I lost the whole part of the session when everyone was being sensible.

"When I got going there were red and yellow flags everywhere."

The session was stopped halfway through when Carlos Iachonelli hit the wall exiting one of the chicanes, while Pastor Maldonado also damaged the left rear of his car in a separate incident with the barriers.

Pantano ended the session fastest, 0.5s clear of the field, with Alvaro Parente and Karun Chandhok next up.

Once Senna did get going, he was not convinced his car was propelling him at full potential - another reason for his lowly position in the times.

"I'm not sure I had full throttle because people were pulling away on the straights in front of me," he said.

"Things have started really well, I'm only two seconds slower than Giorgio."

Pos Driver Team Time Laps 1. Pantano Racing Engineering 1:47.340 13 2. Parente Super Nova Racing 1:47.867 + 0.527 14 3. Chandhok iSport International 1:47.898 + 0.558 13 4. Zuber Piquet Sports 1:47.922 + 0.582 14 5. Di Grassi Barwa Campos Team 1:47.933 + 0.593 15 6. Maldonado Piquet Sports 1:47.944 + 0.604 11 7. D'Ambrosio Dams 1:47.948 + 0.608 14 8. Grosjean ART Grand Prix 1:47.992 + 0.652 15 9. Filippi Trust Team Arden 1:48.362 + 1.022 13 10. Valsecchi Durango 1:48.381 + 1.041 13 11. Petrov Barwa Campos Team 1:48.477 + 1.137 13 12. Rodriguez FMS International 1:48.499 + 1.159 15 13. Valles BCN Competicion 1:48.684 + 1.344 15 14. Villa Racing Engineering 1:48.722 + 1.382 13 15. Soucek Super Nova Racing 1:48.753 + 1.413 14 16. Buemi Trust Team Arden 1:48.893 + 1.553 13 17. Conway Trident Racing 1:49.060 + 1.720 14 18. Senna iSport International 1:49.232 + 1.892 11 19. Yamamoto ART Grand Prix 1:49.459 + 2.119 14 20. Kobayashi Dams 1:49.504 + 2.164 15 21. Valerio Durango 1:49.988 + 2.648 15 22. Herck DPR 1:50.190 + 2.850 15 23. Tung Trident Racing 1:50.297 + 2.957 15 24. Nunes DPR 1:50.326 + 2.986 13 25. Iaconelli BCN Competicion 1:50.623 + 3.283 6 26. Asmer FMS International 1:50.908 + 3.568 15