why does my BMW 3 Series E90/E91 (2005-2012) emit white smoke from the exhaust?

Solution

1. Preparation

• Tools Required: OBD-II scanner, coolant recovery system, compression tester, leak-down tester, basic hand tools.
• Ensure the engine is cool before starting work. Disconnect the battery to prevent electrical hazards.

2. Head Gasket Replacement

• Step 1: Remove Engine Components

  • Disconnect the battery.
  • Remove any engine covers and intake components to access the cylinder head.

• Step 2: Drain Coolant and Oil

  • Drain the coolant from the radiator and engine block.
  • Drain the engine oil from the oil pan.

• Step 3: Remove Cylinder Head

  • Unbolt the cylinder head following the manufacturer's torque sequence.
  • Carefully lift the cylinder head off the engine block.

• Step 4: Inspect and Clean Surfaces

  • Inspect the cylinder head and engine block for warping or cracks.
  • Clean the mating surfaces to remove old gasket material.

• Step 5: Install New Head Gasket

  • Place the new head gasket on the engine block.
  • Position the cylinder head back onto the engine.

• Step 6: Torque Cylinder Head

  • Using a torque wrench, follow the manufacturer's specifications for head bolt torque sequence and values.

• Step 7: Reassemble Components

  • Reinstall any removed components, including the intake and exhaust systems.
  • Refill the engine with fresh oil and coolant.

3. Additional Solutions (if applicable)

• If the issue is related to a cracked engine block or faulty turbocharger (if equipped), replace or repair those components accordingly.