The national average price of regular unleaded remained at $2.85 per gallon for the week ending Sept. 24, even as drivers in 32 states saw lower or stable prices. The price level is 1 cent higher than a month ago and 27 cents above a year ago, according to AAA.

U.S. gasoline demand and supply have declined in September, which has kept the price stable in most regions except for the Great Lakes and Central regions where prices have increased due to maintenance at several refineries, according to data from the U.S. Energy Information Administration. The price of crude oil has begun to increase.

"Crude oil prices pushed past $70/bbl for three days last week," said Jeanette Casselano, AAA spokesperson. "If they trend above this level for a sustained amount of time, we could see a trend reversal in pump prices meaning it may cost more to fill-up as we get closer to the end of the year."

States with the least expensive gasoline include Alabama ($2.53), Mississippi ($2.53), Louisiana ($2.57), South Carolina ($2.58), Tennessee ($2.58), Arkansas ($2.59), Texas ($2.59), Virginia ($2.61), Missouri ($2.61), and North Carolina ($2.68).

States with the largest weekly changes include Delaware (down 8 cents), Kentucky (up 6 cents), Michigan (down 5 cents), North Dakota (up 5 cents), Oklahoma (up 5 cents), Indiana (up 5 cents), Iowa (up 5 cents), Minnesota (up 5 cents), Illinois (up 4 cents), and Nebraska (up 4 cents).

Meanwhile, the average price of diesel increased three-tenths of a cent to $3.271, which is 48.3 cents higher than a year ago, according to the EIA.