After holding steady for two weeks, gasoline prices resumed climbing over the weekend, renewing concern that driving this summer could be more expensive than last year.

Pump prices plateaued around April 1, but began marching upward late last week, said Marie Montgomery, spokeswoman for the Automobile Club of Southern California. Statewide, they're up an average of 5 cents a gallon since Friday.

Ventura County's average price for regular unleaded gasoline stood at $3.32 a gallon Monday, according to The Star's weekly survey of 10 local stations. That's up 6 cents from April 2, when it hit $3.26.

The Auto Club's daily survey also showed the county's average price at $3.32 a gallon, up 6 cents from $3.26 on April 1.

Statewide, the average price was $3.33 a gallon Monday, up 7 cents from April 1. Montgomery said the AAA statewide survey covers prices at about 3,900 service stations.

The rising prices cast doubt on the Federal Energy Administration's prediction last week that pump prices this summer would be slightly lower than they were last year. For a while, she said, that has been the conventional wisdom, but it may not hold.

"As we all know, anything can happen," Montgomery said. "That's the unfortunate reality of all this. We were kind of keeping our fingers crossed last week when we saw that the prices weren't moving anywhere. We thought maybe they'd topped out, but now they've gone up a bit again."

An equipment failure last week at one of California's largest oil refineries apparently was partly to blame for the latest gasoline price increases, said Susanne Garfield, spokeswoman for the California Energy Commission. She declined to identify the company, but said it was forced to buy large quantities of gasoline on the wholesale market to supply its customers.

"Our refiners this year have really been plagued with unplanned maintenance problems. I mean, we just had one after the other and a number of them down," Garfield said. "That has affected production and, obviously, that has affected price. ... This is such a skittish market. It's very sensitive. Production has been severely down over the last eight weeks."

Although they might not like the rising prices, customers at service stations across Ventura County weren't complaining much Monday, several operators said. Most seemed resigned to paying more.

"It's just the usual griping about high prices, you know, but luckily, it's not pointed at me," said Joe Kassar, owner of a Mobil station at Main Street and Mills Road in Ventura, where the price was $3.36 a gallon Monday. "I haven't heard anyone saying they're cutting back on their vacations because of it."

At the 76 station at Victoria Avenue and Telephone Road in Ventura, the price was $3.39 a gallon Monday, up 8 cents since Friday, but there was almost no grumbling, said an attendant, who declined to give his name.

Victoria Chevron down the street posted the same price, a 10-cent increase from last week, and customers weren't happy.

"We're getting complaints, you know that," said Sunny Gahlawat, the station's manager. "They complain, but everybody knows the gas prices are going up, so there's nothing they can do."

David Natanzi, manager of a Chevron station at Los Angeles Avenue and Spring Road in Moorpark, said there were only scattered complaints about his price, $3.40 a gallon. He surmised that most of his customers noticed that the Shell and Mobil stations nearby were charging the same price.

"They can see we're competitive," Natanzi said.

Nationally, the average price for gasoline rose for the 11th straight week, according to a government report released Monday. The U.S. Energy Information Administration said drivers paid an average of $2.876 for a gallon of regular gasoline in the week that ended Sunday, up 7.4 cents from a week ago and up 9.3 cents from a year ago.

Over the past 11 weeks, the national average price has surged 71.1 cents, or 33 percent, from $2.165 on Jan. 29.

On Monday, crude oil prices dipped in volatile trading after election-related violence in oil-producing Nigeria failed to sustain a rally. Nigeria is the eighth largest supplier of oil to the U.S.

Light, sweet crude for May delivery slipped 2 cents to settle at $63.61 per barrel on the New York Mercantile Exchange. Earlier, prices climbed as high as $64.21 and fell as low as $62.55. Brent crude for June fell $1.38 to $67.25 a barrel on London's ICE Futures exchange.

Forecasts for warmer weather in the East and Midwest probably contributed to the crude price fall, an analyst said. How crude oil traders will react to news, the AAA's Montgomery said, is often unpredictable.

"It does seem that the market is more and more attuned to any little blip, any little thing that happens, anything at all," she said. "It's not even necessarily reality. It's the fear of something bad happening. That does seem to be much more of the driver of the price these days."

Kassar, the Mobil station owner in Ventura, said the high prices are affecting his sales. While he usually sells 25,000 to 30,000 gallons of gasoline a week in the spring, Kassar said his sales are down slightly.

He said he thinks that it's because drivers are reducing consumption any way they can.

"People are cutting down on driving and, for people who have more than one car, they use the one that gets better mileage most," he said. "If they have a truck and a car, they park the truck and use the car. It also seems like a lot more people are using motorcycles now."

According to The Star's survey, Ventura County's lowest average price so far this year was $2.53 a gallon on Jan. 29. It hit $3.01 on March 12, about six weeks earlier than last year, when it crossed the $3 line April 19 at $3.10 a gallon.

Last year's peak price was $3.38 a gallon May 15, but the price stayed above the $3 mark until Sept. 11, when it was $2.99 a gallon.

The Associated Press contributed to this report.