why is there water leaking inside my BMW 3 Series E90/E91 (2005-2012)

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the vehicle battery to prevent electrical issues.
• Remove floor mats and any affected interior panels to access the leak source.

2. Clean Sunroof Drains

• Ensure the vehicle is parked on a level surface.
• Locate the sunroof drain tubes (typically at the corners of the sunroof).
• Use a compressed air tool or a flexible wire to clear any blockages in the drains.
• Test the drains by pouring a small amount of water into the sunroof channel and observing for drainage flow.

3. Replace Weather Stripping

• Inspect the weather stripping around doors and windows for damage.
• Carefully remove old weather stripping using a trim removal tool.
• Clean the area with isopropyl alcohol to ensure proper adhesion.
• Install new weather stripping, ensuring a snug fit to prevent water intrusion.

4. Check Windshield Seal

• Examine the windshield for gaps or imperfections in the seal.
• If leaking is identified, carefully peel back the trim and remove the windshield.
• Clean the bonding area and apply new urethane sealant before reinstalling the windshield.

5. Inspect HVAC Components

• Remove the glove box or necessary panels to access the HVAC system.
• Check for clogged drains or leaks from the evaporator case.
• Clear any blockages and replace any damaged components as necessary.