The schedule for the IZOD Indycar Series Shell and Pennzoil Grand Prix of Houston continues to be in flux on Saturday, with qualifying delayed after it emerged that the overnight work intended to tackle the bump in turn 1 of the 1.683-mile, 10-turn temporary street course had failed to entirely overcome the issue.

Concerns were reported by drivers in the USF2000 support race that cars were still at risk of being launched dangerously into the air in the first corner. The IndyCar drivers then undertook an impromptu ten-minute warm-up to check the modifications made overnight to the trouble spot in turn 1 without Friday's temporary tyre chicane in place, and found that their cars too were similarly affected albeit to a lesser degree.

Will Power topped the times for the session with a lap of 1:00.8275s (96.706mph) ahead of Simon Pagenaud, Luca Filippi and James Jakes, but the times weren't directly comparable with Friday practice because of the change in the track configuration.

The chicane was being put back in place in time for the USF2000 race, but was expected to be removed again in time for IndyCar qualifying which was pushed further back in the schedule. Plans to run the usual elimination format culminating in the Firestone Fast 6 has already been shelved because of the delays, with qualifying for both of the doubleheaders now due to consist of two groups running during a split half-hour session to set their fastest lap in the time available, with the fastest driver on pole.

The issue with turn 1 meant that the qualifying session for the Indy Lights support race had already been co-opted as a practice/familiarisation opportunity instead, leaving the race starting with a grid order determined by points standings.

The track problems could also now mean that IndyCar will be unable to stage double-file restarts during the two double-header races because the track is simply too rough to allow this to be done safely. Among the possible alternatives being considered is the idea that both races will now feature standing starts at the beginning and single file restarts thereafter.

Saturday warm-up times

1. #12 Will Power Penske (C) 96.706mph 1:00.8275s (8 laps)
2. #77 Simon Pagenaud Schmidt (H) 95.930mph 1:01.3195s + 0.4920s (8 laps)
3. #98 Luca Filippi BHA (H) 95.897mph 1:01.3411s + 0.5136s (8 laps)
4. #16 James Jakes RLL (H) 95.820mph 1:01.3903s + 0.5628s (7 laps)
5. #18 Mike Conway Dale Coyne (H) 95.746mph 1:01.4373s + 0.6098s (7 laps)
6. #19 Justin Wilson Dale Coyne (H) 95.683mph 1:01.4783s + 0.6508s (8 laps)
7. #5 EJ Viso Andretti-HVM (C) 95.640mph 1:01.5054s + 0.6779s (6 laps)
8. #10 Dario Franchitti Ganassi (H) 95.629mph 1:01.5130s + 0.6855s (8 laps)
9. #9 Scott Dixon Ganassi (H) 95.562mph 1:01.5559s + 0.7284s (5 laps)
10. #14 Takuma Sato AJ Foyt (H) 95.544mph 1:01.5672s + 0.7397s (7 laps)
11. #55 Tristan Vautier Schmidt (H) 95.492mph 1:01.6007s + 0.7732s (5 laps)
12. #7 Sebastien Bourdais Dragon (C) 95.409mph 1:01.6546s + 0.8271s (8 laps)
13. #27 James Hinchcliffe Andretti (C) 94.925mph 1:01.9688s + 1.1413s (6 laps)
14. #3 Helio Castroneves Penske (C) 94.802mph 1:02.0493s + 1.2218s (8 laps)
15. #4 Oriol Servi? Panther (C) 94.711mph 1:02.1087s + 1.2812s (7 laps)
16. #1 Ryan Hunter-Reay Andretti (C) 94.605mph 1:02.1783s + 1.3508s (6 laps)
17. #78 Simona De Silvestro KV Racing (C) 94.445mph 1:02.2838s + 1.4563s (6 laps)
18. #6 Sebastian Saavedra Dragon (C) 94.412mph 1:02.3058s + 1.4783s (6 laps)
19. #15 Graham Rahal RLL (H) 94.384mph 1:02.3242s + 1.4967s (9 laps)
20. #25 Marco Andretti Andretti (C) 94.302mph 1:02.3781s + 1.5506s (7 laps)
21. #83 Charlie Kimball Ganassi (H) 93.998mph 1:02.5798s + 1.7523s (8 laps)
22. #11 Tony Kanaan KV Racing (C) 93.960mph 1:02.6055s + 1.7780s (7 laps)
23. #67 Josef Newgarden SFHR (H) 92.375mph 1:03.6794s + 2.8519s (7 laps)
24. #20 Ed Carpenter Ed Carpenter (C) 92.019mph 1:03.9259s + 3.0984s (6 laps)

Total laps: 168