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10 ways you're killing your car

Jason Notte
April 29, 2014


If your "check engine" light could talk, it might want to hurl obscenities at you for ignoring it when it's only trying to help you out.

Your "check engine" light is your car's means of sitting you down for an intervention. It's trying to tell you that something's wrong and that you need to take action before it gets worse.

If you're like many of us, you're just going to hope that little LED bulb burns itself out so you can go about your business. After all, how bad could it really be? You'd hear something, right? Then you could search "car banging noise" on YouTube and watch an instructional video on how to fix it yourself.

Yeah, this is how car repairs increased for the second year in a row. According to car repair data site CarMD, repairs increased 6.7% overall last year, including a 13% uptick in labor costs and 3% increase in parts costs. In the Northeast and Midwest, where hardy folk who brave the cold regularly should know better, plummeting temperatures brought a 9% increase in average car repair costs last year.

CarMD just released its Vehicle Health Index and looked at what some of the most common "check engine" light repairs were in 2013. The sad fact is that most expensive common repairs could have been prevented by simple, inexpensive, routine maintenance. But since everybody's an expert, here are the problems that all of you self-certified mechanics failed to diagnose within the past year.

1. "Replace Oxygen Sensor(s) (O2S)"
Average repair costs: $261.61

"Inspect for Loose Fuel Cap and Tighten or Replace as Necessary"
Average repair costs: $0.11

"Replace Catalytic Converter(s) with new OE Catalytic Converter(s)"
Average repair costs: $1,154.23

4. "Replace Spark Plug Wires and Spark Plugs"
Average repair costs: $361.95

5. "Replace Mass Air Flow (MAF) Sensor"
Average repair costs: $423.61

6. "Replace Ignition Coil(s)"
Average repair costs: $250.94

7. "Replace Ignition Coil(s) and Spark Plug(s) if needed"
Average repair costs: $420.34

8. "Inspect Battery and Charging System and Repair/Replace as Necessary"
Average repair costs: $110.82

9. "Replace Exhaust Gas Recirculation (EGR) Valve and Clean All EGR Ports"
Average repair costs: $351.97

10. "Inspect For Faulty Vacuum Hose and Replace As Necessary"
Average repair costs: $122

For a detailed breakdown, see the slideshow.

[Related video: Avoid getting ripped off by a car mechanic]