- Coolant temperature sensor: If the coolant temperature sensor is faulty, it may be providing incorrect information to the engine control unit (ECU), which can cause the engine to run rich or lean, leading to misfires.
- Fuel injector: A clogged or faulty fuel injector can cause a cylinder to receive too much or too little fuel, which can lead to misfires.
- Spark plug: A worn or damaged spark plug can cause the engine to misfire.
- Ignition coil: A faulty ignition coil can prevent the spark plug from receiving the necessary voltage to create a spark, leading to misfires.
- Vacuum leak: A vacuum leak can cause the engine to run lean, which can lead to misfires.
- Catalytic converter: A clogged or damaged catalytic converter can restrict the flow of exhaust gases, causing the engine to run rough and misfire.
These are just a few of the possible causes of a car misfiring and running rough after 30 minutes. To accurately diagnose the issue, it is recommended to have the car inspected by a qualified mechanic.
