Heikki Kovalainen failed to add to Lotus’s constructors’ championship tally on his comeback to F1 in place of the absent Kimi Raikkonen.
Kovalainen made a slow start to the race, losing four places from his starting position of eighth, then ran into technical problems with his E21 chassis.
“My start wasn’t great but then it was going okay until the first pit stop as I was racing with the pack with the car feeling quite good,” said Kovalainen.
“After the pit stop I started to have a few problems, but it was difficult to know exactly what was going on. We had issues with downforce so we changed the front wing and after that it was much better, although still not as good as it’s felt previously this weekend.
“There was a KERS issue too, though not enough to account for my lack of race pace.”
Kovalainen finished 15th on the road and was promoted one place by Esteban Gutierrez’s penalty.
He will drive for the team again this weekend in Brazil as they try to overcome their 18-point deficit to Ferrari for third place in the constructors’ championship in the final race of the year. Second place for Romain Grosjean and fifth for Fernando Alonso narrowed the gap between the two teams by eight points in Austin.