2. Check the oxygen sensor. The oxygen sensor measures the amount of oxygen in the exhaust gas. If the oxygen sensor is faulty, it can cause the check engine light to come on.
3. Check the catalytic converter. The catalytic converter converts harmful pollutants in the exhaust gas into less harmful substances. If the catalytic converter is faulty, it can cause the check engine light to come on.
4. Check the spark plugs. The spark plugs ignite the fuel in the engine. If the spark plugs are faulty, it can cause the check engine light to come on.
5. Check the spark plug wires. The spark plug wires carry the electrical current from the distributor to the spark plugs. If the spark plug wires are faulty, it can cause the check engine light to come on.
6. Check the distributor cap and rotor. The distributor cap and rotor distribute the electrical current to the spark plugs. If the distributor cap or rotor is faulty, it can cause the check engine light to come on.
7. Check the fuel injector. The fuel injector sprays fuel into the engine. If the fuel injector is faulty, it can cause the check engine light to come on.
8. Check the mass air flow sensor. The mass air flow sensor measures the amount of air that flows into the engine. If the mass air flow sensor is faulty, it can cause the check engine light to come on.
9. Check the throttle position sensor. The throttle position sensor measures the position of the throttle valve. If the throttle position sensor is faulty, it can cause the check engine light to come on.
If you have checked all of these items and the check engine light is still on, you should take your car to a qualified mechanic for further diagnosis.
