why does my BMW 3 Series G20/G21 (2019-2024) engine light keep coming on

Solution

1. Preparation

• Gather tools and materials: OBD-II scanner, socket set, torque wrench, multimeter, and replacement parts if needed.
• Park the vehicle on a level surface and set the parking brake.
• Disconnect the battery (negative terminal) to ensure safety.

2. Address Error Codes

• Connect the OBD-II scanner to the vehicle's diagnostic port.
• Retrieve and document all error codes.
• Research codes to determine the associated issues (e.g., P0300 for random misfire).

3. Inspect and Replace Components

• Gas Cap:

  • Inspect for damage and ensure it seals properly.
  • Replace if necessary.

• Air Filter:

  • Remove the air filter housing (usually involves removing screws or clips).
  • Replace with a new filter if dirty.

• Ignition Components:

  • Remove spark plug wires/coil packs.
  • Inspect spark plugs for wear; replace if worn or fouled.
  • If coils are faulty, replace them as well.

4. Fuel System Check

• Attach a fuel pressure gauge to the fuel rail.
• Start the engine and check the fuel pressure against manufacturer specifications.
• Replace the fuel filter if clogged or if there are signs of fuel system issues.

5. Reassembly

• Reinstall all components in the reverse order of removal.
• Ensure all connections are secure and that any clips or screws are tightened to manufacturer specifications.

6. Final Checks

• Reconnect the battery (positive terminal first, then negative).
• Clear any error codes using the OBD-II scanner.