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CarMD Releases its 2021 Vehicle Health Index

Catalytic converter replacements most common as average vehicle age increases.

April 21, 2021
CarMD Releases its 2021 Vehicle Health Index

Catalytic converter replacements most common as average vehicle age increases.

4 min to read


IRVINE, Calif. – CarMD.com Corporation, a provider of automotive diagnostic data and business solutions, today released its 2021 CarMD® Vehicle Health Index, an annual overview of check engine light-related repairs, costs and trends. The year 2020 brought many financial challenges for people across the country, which led folks to hold on to older vehicles longer than ever before, and seek to keep their cars and trucks running for as long as possible. These changes impacted the age of vehicles and types of repairs needed.

It's important to remember that while catalytic converters are costly, they don't typically fail unless maintenance and other repairs like as a faulty oxygen sensor or ignition coil are ignored, or a vehicle has high mileage.

This infographic shows the five most common check engine light-related repairs recommended to U.S. drivers in calendar year 2020 and the average cost to make that repair, according to the 2021 CarMD Vehicle Health Index. Each of these issues will negatively impact fuel economy if ignored, which is important to keep in mind as the average price for a gallon of gas inches higher.

The following is a breakdown of the five most common check engine light-related repairs in 2020 and the average cost to make that repair, including parts and labor. Each of these issues will keep a vehicle from passing its state emissions test and negatively impact fuel economy if ignored. This is important to keep in mind as the average price for a gallon of gas in the U.S. is up from $1.95/gallon in April 2020 to $2.88/gallon in April 2021, and inching toward as much as $4.00/gallon in some areas, including California:

  1. Replace catalytic converter(s) with new OE catalytic converter(s), $1,3832)      

  2. Replace oxygen sensor(s), $2433)      

  3. Replace ignition coil(s) and spark plug(s), $3894)      

  4. Replace mass air flow sensor, $3365)      

  5. Tighten or replace fuel cap, $25

"We want vehicle owners to utilize the information provided by CarMD to become informed  about the importance of being attentive to scheduled maintenance and addressing check engine light issues in a timely manner, which can positively impact fuel economy, extend vehicle life, reduce the likelihood of future repairs and make it easier to pass a smog test," said David Rich, CarMD technical director. "We don't want people to panic when they hear that catalytic converters are the most common repair. It's important to remember that while catalytic converters are costly, they don't typically fail unless maintenance and other repairs like as a faulty oxygen sensor or ignition coil are ignored, or a vehicle has high mileage."

According to the National Insurance Crime Bureau, the pandemic has seen a rapid rise in catalytic converter theft because they contain precious metals such as rhodium that can be sold to metal recyclers. In 2019, an average of 282 catalytic converters were stolen every month; in 2020 the average had risen to 1,203. Rich adds that the uptick in catalytic converter replacements and need for these parts can be partially explained by the increase in the average vehicle age to an all-time high of 11.9 years in 2020. As people keep their cars and trucks longer, the automotive aftermarket will need to adjust related parts supply forecasts accordingly. CarMD offers a free online vehicle inspection service available at https://www.carmd.com/wp/garage/ to get service information, predictive failures, recalls, technical service bulletins and other proactive vehicle health information.

Other findings detailed in the 2021 CarMD Vehicle Health Index:

  • In 2020 car repair costs were down 1.6% overall at an average of $378.77. Labor costs were down 2.8% year-over-year from 2019 to 2020, and parts costs were down about 1%. Many factors likely played a role in this decrease, including the economy, competition among repair shops and an increase in DIY automotive repairs during the pandemic. CarMD anticipates an increase in parts costs next year given the material shortage resulting from shutdown-related supply chain issues.

  • New this year CarMD broke down the Index by vehicle model year. Model year 2007 vehicles were most likely to need check engine light repairs, accounting for 9.9% of problems seen by CarMD across all models last year. As many as 29% of inspected model year 2007 vehicles had a check engine light on. A vehicle will not pass its emissions test, required by most states to register a vehicle, if the check engine light is on. The most commonly diagnosed repair on a 2007 vehicle was "replace ignition coil(s) and spark plug(s)." Not surprisingly, vehicles that are less than 3 years old didn't experience many check engine light issues, accounting for fewer than 1% of needed repairs reported to CarMD. 

  • CarMD's data reports an increase in mass air flow sensors (MAF sensors) needing replacement, while fuel cap issues continue to trend down. MAF sensors moved from the no. 5 to the no. 4 most common repair. Gas cap issues dropped again moving from the no. 4 to no. 5 most frequent repair. This and other national and regional trend data in the full report can inform automotive parts suppliers, aftermarket retail buyers and other industry experts as they extrapolate year-over-year and trends related to vehicle diagnostic data and related parts failures.

READ: Weekly Market Insights Report

Topics:Fixed Ops

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