Top 10 reasons your check engine light is on

According to Bankrate.com, when that check engine light comes on it could be serious. Or it could be nothing.

Here are the top 10 check-engine-repairs.

1. Failing oxygen sensor - $261
2. Loose fuel cap - $0.11
3. Failing catalytic converter - $1,154
4. Bad spark plugs and wires - $361
5. Malfunctioning mass air flow sensor - $423
6. Faulty ignition coil - $250
7. Faulty ignition coil and spark plugs - $420
8. Dead battery and charging system - $110
9. Faulty exhaust gas recirculation valve - $352
10. Faulty vacuum hose - $122

A malfunctioning mass air flow sensor? I didn't even know I had one of these. Can I just take the 11 cent loose fuel cap please? To read more about these repairs go here.