why does my BMW X5 F15 (2014-2019) have a rough idle when cold

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to ensure safety while working on electrical components.
• Allow the engine to cool down before starting work.

2. Inspect and Replace Spark Plugs

• Remove the ignition coil covers (if applicable) using a socket set.
• Use a spark plug socket to remove the spark plugs.
• Inspect for wear or fouling; replace with OEM spark plugs if necessary.
• Torque new spark plugs to manufacturer specifications (typically around 25 Nm).
• Reinstall ignition coils and covers.

3. Clean or Replace MAF Sensor

• Disconnect the MAF sensor electrical connector.
• Remove the MAF sensor from the air intake tube.
• Clean the MAF sensor with MAF cleaner (do not use any other cleaner).
• If cleaning does not resolve the issue, replace the MAF sensor with a new one.
• Reinstall the MAF sensor and reconnect the electrical connector.

4. Inspect and Replace Engine Coolant Temperature Sensor

• Locate the coolant temperature sensor on the engine.
• Disconnect the electrical connector from the sensor.
• Remove the sensor using a wrench or socket.
• Install the new coolant temperature sensor and torque it to specifications.
• Reconnect the electrical connector.

5. Check and Clean Fuel Injectors

• Remove the fuel injectors from the fuel rail.
• Inspect for any clogs; clean with a fuel injector cleaning kit if needed.
• Reinstall or replace injectors as necessary, ensuring proper sealing and torque.