What Causes Rough Idling and Engine Misfire in BMW 2 Series?

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What Causes Rough Idling and Engine Misfire in BMW 2 Series?

My BMW 2 Series sometimes has a rough idle, and I feel slight vibrations while the engine is running. Occasionally, I also get engine misfire warnings. Could this be due to spark plugs, ignition coils, o r fuel injector issues? What is the best way to diagnose and resolve rough idling problems in the BMW 2 Series?

Garitips asked on 13 Feb 2025 16:06:30 pm

1 Answer

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Garitips - on 13 Feb 2025 16:07:03 pm

Possible Causes:

Faulty Spark Plugs: Worn o r dirty spark plugs can cause rough idling and misfires.
Ignition Coil Failure: A weak o r failing coil can lead to poor combustion.
Dirty o r Clogged Fuel Injectors: If fuel injectors are clogged, they won’t deliver the right amount of fuel.
Vacuum Leaks: A vacuum leak in the intake manifold can disrupt the air-fuel mixture.
Faulty Mass Airflow Sensor MAF: If the MAF sensor gives incorrect readings, the engine may run rough.
Bad Oxygen O2 Sensor: An O2 sensor failure can cause incorrect fuel mixture adjustments.
Solution:

Check and replace spark plugs if they are old o r damaged.
Test the ignition coils and replace any failing ones.
Clean o r replace dirty fuel injectors.
Inspect the intake manifold and vacuum hoses for leaks.
Clean o r replace the mass airflow sensor if needed.
Replace the oxygen sensor if faulty.