Many commuters are already turning to public transportation.
The MTA said in January, bus ridership spiked 3 percent and rail ridership was up 8 percent. Officials expect even more of a rush this month.
"It's too expensive. Four, almost $5 - that's a lot of money, especially when you don't have a job," said Daya Sheriff of Compton.
Metro doesn't have its numbers for February yet, but its numbers for January of this year compared to January of last year shows a big change.
"Our ridership is up now 4.6 percent over a year ago. As gas prices continue to climb, we'll see a steady increase of riders," said Metro spokesperson Marc Littman.
Many Metro riders said they're not so concerned with reducing their carbon footprint but with the cost to drive.
"I noticed earlier this week that they were almost up to $4 and I could have sworn they were just at $3.25 or $3.30 a while ago. I am completely caught off guard," said Kevin Scheller of Encino.
In Southern California, prices are at some of their highest levels in years. Since last week, the price of gas in Los Angeles and Long Beach rose by 20 cents to $3.77, according to the Auto Club of Southern California. Prices also increased by about the same amount in Orange and Ventura counties and the Inland Empire to $3.76.
Dan Zehfuss of Santa Clarita said he's been taking the bus since last week because of gas prices.
"It's certainly not as convenient. It takes me quite a bit longer, and it's not quite as comfortable," he said.
Oil prices now cost about $97 a barrel, down from more than $100 a barrel last week. Instability in the Mideast continues to make investors nervous.
As for the U.S. economy, there's concern that if the prices continue to rise, it's going to put a break on the economic recovery.