why does my BMW 3 Series F30/F31 (2012-2019) have a rough start in the morning

Solution

1. Preparation

• Gather necessary tools and parts.
• Ensure the vehicle is parked on a flat surface and the engine is cool.
• Disconnect the negative battery terminal for safety.

2. Battery Inspection and Replacement

• Tools Required: Multimeter, battery terminal cleaner, wrench set, replacement battery (if needed).
• Check the battery voltage using a multimeter; it should read above 12.4 volts.
• Clean the battery terminals with a terminal cleaner or wire brush.
• If the battery is weak (below 12.4 volts), remove it using a wrench, replace it with a new battery, and reconnect the terminals securely.

3. Fuel System Check

• Tools Required: Fuel pressure gauge, screwdrivers, safety goggles.
• Locate the fuel pressure test port and attach the fuel pressure gauge.
• Turn the ignition to the "on" position without starting the engine; check that the pressure meets specifications (typically 50-60 psi for most models).
• If pressure is low, inspect and replace the fuel pump or filter as necessary.

4. Ignition System Inspection

• Tools Required: Spark plug socket, torque wrench, multimeter.
• Remove the ignition coils and inspect for cracks or damage.
• Test the spark plugs for wear; replace if they are worn or fouled.
• Reinstall ignition components and torque them to manufacturer specifications.

5. Oil Inspection and Change

• Tools Required: Oil filter wrench, drain pan, socket set.
• Check the engine oil level and condition. If it appears dirty or is low, replace it.
• Drain the old oil and replace it with the correct grade oil for cold starts (consult owner's manual).
• Replace the oil filter during this process.