The 22-year-old Invercargill driver described his weekend at the second round of the Formula 4 US Championship as ''very up and down''.
Racing at the Indianapolis Motor Speedway, he finished 13th and 14th in the first and last of three 30-minute races.
He had looked as if he would finish fourth in the second race, but his car ran out of fuel.
Earlier he had been the fourth-quickest of the 30 competitors at the first practice and was seventh in the second practice.
He and others were hampered in the 30-minute qualifying session which was run primarily under caution. That limited the chance for a fast lap.
He qualified 12th, but was handed a 10-place grid penalty - along with five others - for allegedly causing a collision at the previous round in Miami.
''The decision was made based on poor footage,'' Leitch said.
''After reviewing some newly found footage last week, they [stewards] realised they had made a mistake but weren't willing to reverse the decision.
''Bit of a shame, but that's how it goes sometimes, unfortunately.''
He said the competition in the championships was varied and he was really happy with his second race.
''There are some very good drivers, no doubt. But being a very fresh series, there are some very new drivers who don't have lots of experience in racing as of yet, so you're certainly aware of this.
''I was really happy with our speed in race two.
''Even though it didn't end well, we showed our speed and I'm really excited for the next round.''
Leitch will return to New Zealand before heading to Ontario, Canada, for round four of the championship early next month.
