Simon Pagenaud has been given a 10-place grid penalty for Sunday's IndyCar season opener at St. Petersburg after his team made an engine change following Friday's second free practice session.
The Frenchman pulled over to the side of the track during the session after hearing a noise and shut the car off in the hope of preventing further damage.
"Something didn't feel right, and I shut it down to be on the safe side," he said.
But after analyzing the problem, the Schmidt-Hamilton Motorsports team opted to swap the Honda unit, incurring a 10-place penalty for breaching rule 15.6.1 of the sporting regulations. That rule prevents unapproved engine changes except in the event of an engine failure.
Engine problems had been widely tipped to be a feature of this weekend's race due to the short development times, although Pagenaud's team is the only one to have encountered any issues so far.