why does my BMW 3 Series F30/F31 (2012-2019) have poor acceleration after a cold start

Solution

1. Preparation

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

2. Inspect Air Intake System

• Remove the air filter housing and inspect the air filter for clogs or excessive dirt.
• Clean or replace the air filter as necessary.
• Inspect the intake duct for cracks or leaks, and replace if damaged.

3. Check Fuel System

• Connect a fuel pressure gauge to the fuel rail.
• Turn the ignition to the "ON" position without starting the engine to check the fuel pressure.
  • Specification: Fuel pressure should typically be around 50-60 psi (check manufacturer specifications).
• If the pressure is low, inspect the fuel pump and fuel filter for blockages or failures.

4. Replace Ignition Components

• Remove the ignition coils and inspect the spark plugs for wear or fouling.
• Replace spark plugs if worn or damaged, using OEM or equivalent parts.
• Reinstall ignition coils ensuring proper seating and connection.

5. Check Engine Coolant Temperature Sensor

• Locate the coolant temperature sensor and disconnect the electrical connector.
• Use a multimeter to test the sensor's resistance at various temperatures to ensure it is functioning correctly.
• Replace the sensor if it does not meet specifications.

6. Reassemble and Test

• Reconnect all components and ensure there are no loose connections.
• Reconnect the battery.
• Start the engine and allow it to reach operating temperature, then test acceleration performance.