The state is trying to reduce emissions by 80 percent from 1990 levels by 2050.
California legislators are preparing a bill that proposes a 2040 target for outlawing sales of gasoline and diesel vehicles.
The Volkswagen diesel emissions crisis has sparked broader action against internal combustion engines, with sales bans promised in China and several European countries.
California Governor Jerry Brown reportedly asked state officials why China can make such a move but not California.
Legislators responded by picking the year 2040 and writing up a bill to introduce in Sacremento in January.
"Until you set a deadline, nothing gets done," state Assemblyman Phil Ting told Bloomberg. "It's responsible for us to set a deadline 23 years in advance."
California's clean-air legislation has served as a framework for more than a dozen other states. It is unclear if such a proposal will be mimicked outside of Tesla's home state, however.