Car Idling Rough Check Engine Light On: Causes and Solutions

If your car is idling rough and the check engine light is on, it could be a sign of a serious problem. There are many potential causes of this issue, so it’s important to get your car diagnosed by a mechanic as soon as possible.

Possible Causes of Car Idling Rough Check Engine Light On

Vacuum leaks. A vacuum leak can cause your car to idle rough by allowing unmetered air to enter the engine. This can disrupt the air-fuel mixture and cause the engine to run lean or rich.
Fuel injector problems. Fuel injectors are responsible for delivering fuel to the engine. If a fuel injector is clogged or malfunctioning, it can cause the engine to idle rough.
Spark plug problems. Spark plugs are responsible for igniting the air-fuel mixture in the engine. If a spark plug is worn out or malfunctioning, it can cause the engine to idle rough.
Ignition coil problems. The ignition coil is responsible for providing the spark plugs with the voltage they need to ignite the air-fuel mixture. If the ignition coil is malfunctioning, it can cause the engine to idle rough.
Mass air flow sensor problems. The mass air flow sensor (MAF) is responsible for measuring the amount of air entering the engine. If the MAF is malfunctioning, it can cause the engine to idle rough.
Oxygen sensor problems. The oxygen sensor is responsible for measuring the amount of oxygen in the exhaust gases. If the oxygen sensor is malfunctioning, it can cause the engine to idle rough.
Catalytic converter problems. The catalytic converter is responsible for reducing the emissions from the engine. If the catalytic converter is malfunctioning, it can cause the engine to idle rough.

Solutions for Car Idling Rough Check Engine Light On

The solution to a car idling rough with the check engine light on will depend on the underlying cause of the problem. However, some general solutions include:

Fixing vacuum leaks. Vacuum leaks can be repaired by replacing the damaged hoses or gaskets.
Cleaning or replacing fuel injectors. Clogged fuel injectors can be cleaned using a fuel injector cleaner. Malfunctioning fuel injectors will need to be replaced.
Replacing spark plugs. Spark plugs should be replaced according to the manufacturer’s recommended maintenance schedule.
Replacing the ignition coil. A malfunctioning ignition coil will need to be replaced.
Cleaning the mass air flow sensor. The MAF can be cleaned using a MAF cleaner.
Replacing the oxygen sensor. A malfunctioning oxygen sensor will need to be replaced.
Replacing the catalytic converter. A malfunctioning catalytic converter will need to be replaced.

Conclusion

If your car is idling rough and the check engine light is on, it’s important to get your car diagnosed by a mechanic as soon as possible. The cause of the problem could be serious, so it’s best to address it right away.