CarMD American Vehicle Health Index: First jump in car repair costs in six years Corp., a provider of car repair data, released its 2013 CarMD Vehicle Health Index™ ranking of check engine-related car repairs and costs for model year 1996 to 2012 vehicles. For the first time in six years, car repair costs jumped 10 percent nationwide to $367.84 on average per repair.

The no. 1 most common repair remains a faulty oxygen sensor, which can reduce fuel economy by as much as 40%. With gas prices and repair costs rising, this annual Index sheds light on vehicle failure data and repair trends that impact safety, reduce fuel economy and can result in more expensive and spiraling repairs if left unaddressed.

“On one hand we’re seeing an increase in car repair costs that can be attributed to factors such as a market correction and a higher percentage of more expensive repairs related to the aging vehicle population, but on a more positive note we see costs for hybrid repairs continuing to drop and drivers making fewer check engine-related trips to the repair shop,” said Ieon C. Chen, CEO, CarMD. “The broad findings in the CarMD Vehicle Health Index can empower consumers to extend vehicle life through informed repair and maintenance decisions. Whether you make repairs yourself or seek service from a trusted professional, the most common check engine-related repairs demonstrate that addressing small problems early is key to saving time and money.”

The 2013 CarMD Vehicle Health Index analyzes more than 161,000 repairs input and validated by CarMD’s nationwide network of ASE-certified technicians from Jan. 1, 2012 to Dec. 31, 2012. The full Index is available at

Last year saw a 10 percent increase in car repair costs to pre-recession rates, with parts up 6 percent and labor costs rising 17 percent. The hardest hit region was the Northeast with an 11.56 percent increase.

  • With average vehicle age now surpassing 11 years, costly and catastrophic repairs continue to rise. The 15 most expensive repairs saw a 24 percent jump in frequency.
  • For the first time, battery and charging system problems appeared in the top 10 most common check engine-related repairs moving from no. 10 to no. 16, partially due to computers on newer models that now track insufficient charging voltage, including failing batteries and alternators. Car batteries are also susceptible to heat, as are many other car parts such as cooling systems, transmissions and a range of fluids. As the U.S. logged its hottest year on record in 2012, the Index data demonstrates the effects of heat on vehicle parts and the need for drivers to adapt their maintenance routines accordingly.
  • Recall-related repairs have also emerged among common repairs, as have fixes related to newer systems such as antilock brakes and residual effects of parts failing due to the effects of higher percentage ethanol-blend fuels.

Manufacturers are making cars and their parts to last longer with longer maintenance and repair intervals. This coupled with consumers becoming savvier in addressing minor car repairs from home has resulted in a 1.3% drop in check engine-related trips to the repair shop last year.


  • Hybrid repair costs continue to drop with increased volume of hybrids on the road, and parts and people qualified to service them. The most expensive repair in 2011 was “replace hybrid inverter assembly” at $4,098, which decreased by nearly 5 percent in 2012. Hybrid repairs no longer hold the top spot, which is now “Replace Transmission Assembly and Reprogram Electronic Control Module” at more than $5,400.
  • Vehicle owners are also taking care of diagnosing and repairing smaller problems, like the pesky loose gas cap, themselves.

As fuel prices rise, CarMD’s Index accentuates the need for consumers to be aware that driving with the check engine light on often indicates a problem that can negatively impact fuel economy. The top five most common check engine-related problems reduce fuel economy and often escalate into more serious problems if left unrepaired.


  1.   The most common repair, “replace oxygen sensor” can lead to a 40 percent reduction in gas mileage if ignored, which equates to roughly $1.50 per gallon or $900 per year in extra fuel costs. A faulty O2 sensor can also lead to costly catalytic converter damage.
  2. The second most common repair is “tighten or replace gas cap.” Loose or missing gas caps cost drivers time and money, triggering the check engine light and a repair shop visit, and a 0.5 percent decrease in gas mileage.
  3. “Replace catalytic converter(s)” rose 7 percent to $1,101.44 on average. In most cases, a catalytic converter won’t fail unless a related part such as a spark plug or O2 sensor is ignored for too long. A damaged catalytic converter can result in fuel consumption loss up to 20 percent and eventually cause a vehicle to quit working altogether.
  4. “Replace ignition coil(s) and spark plug(s)” costs increased nearly 7% from $296.87 in 2011 to $316.58 in 2012. As the fourth most common repair, Ignition coils often fail due to bad spark plugs resulting in the replacement of both parts. They can also decrease fuel economy by up to 20 percent, costing drivers an extra $450 per year extra at the pump given today’s gas prices.
  5. The small but mighty spark plug returns to the top 5 list this year. The average cost to replace spark plugs and wires jumped nearly 9 percent this year. Ignore a spark plug and risk ignition coil and eventual catalytic converter damage, as well as roughly a 2 percent reduction in fuel economy.

CarMD’s free Vehicle Health ScoreCard tool, available at, helps consumers gauge their vehicle’s health, and gain access to the most common repairs and related costs for their specific vehicle.
Beginning in 1996, the government mandated on-board diagnostics (OBD2) for all foreign and domestic cars, light trucks, minivans, SUVs and now hybrids sold in the U.S. This technology detects malfunctions, sets a diagnostic trouble code (DTC) and turns on the check engine light if a problem is detected. The system is currently installed on about 85 percent of vehicles nationwide. CarMD’s network of Automotive Service Excellence (ASE)-certified technicians has built the largest, most up-to-date-database of DTCs, expert fixes and repair costs.

This database, from which CarMD draws its Vehicle Health Index, adds and validates more than 500 new repairs daily. It is released each April in conjunction with National Car Care Awareness Month to provide vehicle owners and the industry with a comprehensive and independent report on vehicle repair trends. This 2013 Index statistically analyzes more than 161,000 repairs. For more information, including the complete Index, methodology and archived data, visit