Scott Matthews' wife didn't understand why he insisted on keeping a fire extinguisher in his car — until Sunday.

While driving in Newport Beach en route to Costa Mesa — his wife and 13-year-old daughter also in the car — he thought he saw a house fire in the 1600 block of Irvine Avenue.

But after getting closer to the scene, Matthews, a 32-year employee of the Newport-Mesa Unified School District, and his family soon found out it was a white Bentley on fire.

Furthermore, the car, with five-foot-high flames coming from the engine compartment, was only a few feet away from the house.

The Bentley's owner, who had used up his own fire extinguisher in battling the blaze, was waiting for the Fire Department.

Despite concerns about a gasoline explosion, Matthews, 55, stopped the car and grabbed his own extinguisher.

"I thought, you know, what if you don't get this? The house could burn down," he said. "You have a minute to do what you can."

In his efforts, Matthews sustained burns on his calf after pulling off the car's cover that stuck to his leg.

In the end Matthews, a custodian at Harbor View Elementary and Estancia High alumnus, put out the car fire and a secondary fire on a patch of grass just before Newport firefighters arrived. They had received a call at 12:14 p.m. about the fire, said department spokeswoman Jennifer Schulz.

Seeing some good work already finished, Matthews said the firefighters gave him high-fives.

Furthermore, Matthews had won an old argument with his wife: why he travels with a fire extinguisher.

"The rest of the night it was, 'See! I told you,'" Matthews said.

Later that evening, the woman who owns the Irvine Avenue house arrived at Matthews' home with a thank-you gift: two new fire extinguishers.

"She was really grateful; her husband too," Matthews said. "I was glad to do it."

britney.barnes@latimes.com

Twitter: @britneyjbarnes