Replace oxygen sensors
Average repair cost: $259.30
Oxygen sensors remained the most common car repair, accounting for 7.1% of repairs in 2014. The O2 sensor can fail because of neglecting car repairs, internal engine leaks or burning oil, or by using gas with a higher ethanol concentration. A malfunction can cause as much as a 40% drop in fuel economy and can affect performance. The average cost of the repair decreased $2 from the prior year.