(June 30, 2011) FOUNTAIN VALLEY, Calif. (PRNewswire) — In 2010, drivers in Arizona paid the most in the nation for car repairs at an average cost of $421.49, according to CarMD.com Corporation, which analyzed roughly 80,000 repairs made on vehicles with "check engine" light problems in 2010.

Arizona's no. 1 ranking is 18% more than the U.S. average for overall costs and 23% more for parts. Drivers in the District of Columbia, which is one of the wealthiest areas in the country (according to the most recent U.S. Census Bureau), paid the least at $265.29 per transaction.

CarMD also found that drivers in New Jersey pay closest to the national average for car repair costs at $357.32, just a dollar more than the U.S. average. According to the first annual CarMD Vehicle Health Index, the average cost of U.S. "check engine"-related auto repairs in 2010 was $356.04, including $212.44 in parts and $143.61 in labor costs.

"Through comprehensive data collected via CarMD's nationwide network of Automotive Service Excellence-certified technicians, we are able to provide national and state-by-state transparency into vehicle repair costs," said Art Jacobsen, vice president, CarMD.com Corporation.

"We are releasing this data to empower consumers and technicians with a better understanding of common repairs and costs, and to call attention to the fact that, regardless of region, drivers who follow a regularly scheduled maintenance program and address small problems early tend to have reduced fuel bills and repair costs. 

"That said, if you live in a state with harsh weather conditions such as Arizona's heat or North Dakota's cold, it's imperative to take care of your car to avoid catastrophic vehicle failures."

Several interesting highlights emerge when comparing costs and ranking repairs for each state. While Arizona's no. 1 ranking can be attributed to warm, dry weather, which wreaks havoc on the longevity of a car's parts, it is surprising to see Arizona's average parts costs at 23% higher, and California's labor costs 20% higher than the U.S. average.

Western states round out the top five most expensive spots, with only three non-western states listed in the top 10, including North Dakota at no. 8, Rhode Island at no. 9 and South Dakota at no. 10. Drivers in the western U.S. paid about 13% more than drivers in the Midwest, 11% more than drivers in the Southeast and 5% more than those in the Northeast for repairs.

Labor costs in the West tend to be higher due to dry air, build up and dust, such as clogged mass airflow sensor, which occurs more frequently and increases costs. Milder temperatures in Western states also allows for more year-round driving, which leads to added wear and tear.

The following is the ranking of the top 5 states with the highest car repair costs in 2010, according to CarMD:

CarMD ranking of states/districts with the lowest car repair costs in 2010:

Other key findings:

    • Six of the 10 states with the lowest car repair costs are from the Midwest, including Nebraska, Wisconsin, Ohio, Missouri, Indiana and Minnesota.

    • The states with lower repair costs had more gas cap-related problems. A loose gas cap, which is one of the most common causes for check engine problems, accounted for nearly 12% of repairs in D.C. and 11% in Ohio. Loose, damaged or missing gas caps are an inexpensive fix but cause 147 million gallons of gas to evaporate annually.

    • More than 12% of the repairs in D.C. were made at zero cost in terms of parts and labor charges, likely because of a higher number of vehicles that are new or under manufacturer's warranty.

    • Several states with lower repair costs had a substantial number of repairs that did not require any parts at all, including Missouri (26%) and Wisconsin (21%). Some of these repairs were made under warranty at no charge, while others were "check engine" light issues that could be fixed with a simple adjustment such as "tighten gas cap," "adjust idle," "remove aftermarket alarm" and "clean throttle body."

    • Drivers in Alaska paid the most ($268.22) for oxygen sensor replacement, which was the no. 1 most common repair in the country in 2010. O2 sensors monitor the amount of unburned oxygen in the exhaust and tell a car's computer how much fuel to inject for proper operation. If a faulty O2 sensor is not repaired, the car's fuel economy will dramatically drop. The average cost to replace an O2 sensor is $238.71, including parts and labor, but can lead to as much as a 40% reduction in gas mileage.

The CarMD State-by-State ranking of average repair costs was derived from analysis of roughly 80,000 repairs made from Jan. 1, 2010 through Dec. 31, 2010 by CarMD's network of Automotive Service Excellence-certified technicians. 

The Census Regions and Divisions of the U.S. map was used for regional data calculations.  The repairs are all related to a vehicle's "check engine" system, which is designed to alert drivers to large and small problems that affect emissions output and drivability. This technology is standard on all vehicles manufactured since 1996 and covers an estimated 80% of systems on cars, trucks, SUVs and minivans – foreign and domestic.

The CarMD database and average cost of repair findings does not include repairs of problems that are not associated with a vehicle's on-board diagnostic computer such as tires, brakes and mechanical parts such as belts and hoses.