U.S. vehicle owners paid 6.5% more to repair “Check Engine” light issues in 2018, according to the latest Vehicle Health Index from Irvine, CA-based CarMD.

The average cost to repair a “Check Engine” problem nationally was $380.85 ($223.81 for parts and $157.04 for labor), representing a 3.5% uptick in parts costs and an 11.2% rise in labor costs when compared to the previous year. Repair costs were up across all regions.

In 2018, drivers in the West paid the most at $386.78 (up 8.0%), followed closely by the South at $385.46 (up 7.8%). The Northeast came in at $379.76 (up 4.9%). Drivers in the Midwest paid the least at $366.31 (up 1.0%).

For the first time since CarMD has reported its rankings, there was a tie for the No.-1 most commonly diagnosed “Check Engine” light repair with “replace ignition coil/coils and spark plug/spark plugs” (up from No. 2 in 2017) and “replace oxygen sensor/sensors” (no change when compared to 2017). Each accounted for 5.81% of repairs in 2018.

Rounding out the five most common problems found to trigger the “Check Engine” light were …
• Replace catalytic converter/converters and new OE catalytic converter/converters at 4.93% (no change when compared to 2017).
• Inspect for loose fuel cap and tighten or replace as necessary at 4.18% (no change from 2017).
• Replace ignition coil/coils without spark plug replacement (up from No. 7 in 2017).

Notably, there were slightly fewer mass air flow sensor and EVAP purge control valve replacements in 2018.

The most common repair in the West, Midwest and Northeast regions was “replace oxygen sensor/sensors,” while it was “replace ignition coil/coils and spark plug/spark plugs” in the South.

The latest Vehicle Health Index analyzed repairs needed on nearly 7.17 million in-use vehicles reported to, and validated by, CarMD’s network between Jan. 1, 2018 and Dec. 31, 2018. Click here to view the full index, including the 10 most common “Check Engine” related repairs, 10-year history of U.S. repair costs, most common repairs by region, and 10 least/most expensive repairs.