For the last several years, more than 85,000 hybrid car drivers were able to use the carpool lanes by themselves, but that privilege has ended. Officials said they will now cite drivers who violate the law.
The yellow sticker program, which started in 2004, was so popular that it reached its capacity and the state stopped issuing stickers in 2006.
The Department of Motor Vehicles said it will add new stickers in 2012 that will allow solo drivers of cars with even higher fuel emission standards to get into the carpool lane. But the state has not decided on what cars those will be.
Another traffic change is that the state will be clamping down on repeat offenders. Before, if you got a ticket for something, like speeding, you can opt to take traffic school to clear your record.
But now the state said it will keep better track of the convictions. If you're cited again within 18 months, you will not be able to take traffic school and judges will see your original conviction on your record.
Also on Friday, the state sales tax is dropping from 8.25 percent to 7.25 percent, which means Californians will pay one cent less on sales tax for every dollar they spend.
And the fee to register a new car is dropping by half a percent, which is great news for car dealers.
Gov. Jerry Brown had worked for months to extend the temporary tax increases that were passed in 2009, but he couldn't find Republican support.
Brown, who signed a rare on-time state budget Thursday, said there's a cost to signing a budget without them, such as cuts to education and services to the elderly.
"These are really tough, hard decisions, and going forward, we're going to have to ask Californians about what is it that we want," said Brown.