A recent article in the Arizona Republic reported that one in ten vehicles has a check engine light on at any one time, and that once the light appears, sometimes it takes up to three months for the owner to get it checked out at their local auto repair shop. For most of us, when we see the check engine light go on in our car, our first reaction may be to ignore it.  But doing so could not only be damaging to your vehicle but damaging to your wallet as well.
A very common reason the check engine light goes on is because your gas cap is either not tightened enough or it’s cracked, causing gas to evaporate into the air and waste fuel. A new gas cap costs around $13. But, if the gas cap isn’t the issue, your check engine light could be on because a part in your car needs to be replaced. Here is a list of parts that might cause your check engine light to go on if they’re damaged.
1) Oxygen Sensor – The oxygen sensor measures oxygen in the car’s exhaust, helping to regulate how       much fuel the engine needs to operate. If the oxygen sensor is faulty the car will use more fuel than     necessary and raise fuel costs.
2) Spark Plugs and Catalytic Converter – If the spark plugs are not replaced when needed, damaged     plugs can cause the engine to misfire and lead to catalytic converter problems. If the catalytic     converter does get damaged it can cost up to $2,000.
3) Mass Air Flow Sensor – This measures air coming into the engine. Problems with it can be prevented     if the air filter is changed regularly, typically when you get your oil changed; it usually costs around     $20. If you don’t change the air filter, dust can build up in it and could cost up to $400 to repair.