The Venturi Formula E team has replaced 1997 Formula 1 champion Jacques Villeneuve with Mike Conway ahead of next month's Buenos Aires round.
Venturi confirmed the Canadian's exit on Twitter, citing a "disagreement over the future direction of the team".
Conway, a podium finisher with Toyota's LMP1 team in the World Endurance Championship last season, will compete in the remaining eight rounds of the current Formula E campaign.
The British driver, 32, has prior experience of a Formula E car having tested for Dragon Racing in 2014.
Villeneuve joined Venturi ahead of the second Formula E season but leaves having failed to score a point in the first three rounds.
He was taken out of the opening Beijing ePrix, suffered a pitstop problem in Putrajaya and did not start the last race in Punta del Este after a qualifying crash.
Speaking to Autosport in Uruguay, Villeneuve had hoped the event's post-race test would offer the opportunity to turn his season around.
"I'm not worried, I just hope we can get a good weekend where we can show where we can be," he said.
"When we were testing at Donington I had no idea what I was working on and it's not the best track anyway to prepare for FE. The test will be very useful because I know exactly what to look for and what to work on.
"On paper it looks crap, which I'm aware of and it's frustrating, but we know how competitive we were."