Alexander Sims topped the timesheets in New York in the first free practice session on Saturday morning.
The BMW i Andretti Motorsport driver posted a time of 1:09.959 on a qualifying run at 250 kW run in the closing stages to go 0.018 seconds quicker than Sebastien Buemi’s Nissan e.dams entry.
Robin Frijns’s Virgin Racing entry placed third ahead of Jean-Eric Vergne’s DS Techeetah.
Championship leader Vergne had a fraught session as he endured two lock-ups at Turn 6, but was not the only driver to struggle there, as Antonio Felix Da Costa and Daniel Abt had moments at the same corner.
Despite the lock-up, Da Costa claimed fifth while the Portuguese’s fellow title contender Mitch Evans took his Panasonic Jaguar Racing car to sixth.
Edorado Mortara ended the session in seventh for Venturi with Vergne’s teammate Andre Lotterer in eighth.
Oliver Rowland ended the session ninth with Stoffel Vandoorne in tenth.
Free Practice 2 will get underway at 10:00 a.m. local time for an additional 30 minutes of track running ahead of qualifying which begins at 11.45 a.m.