Smoking from the Coolant Cap: Blown Head Gasket?

Oceanside Motorsports • November 14, 2023

If you’re seeing smoke coming from the coolant cap on your vehicle, it could be a sign of a few different issues, one of which could be a blown head gasket. Here are some possibilities:

  • Blown Head Gasket: 

This is a common cause of smoke coming from the coolant cap. A blown head gasket can allow coolant to leak into the combustion chamber, resulting in white smoke. It can also cause overheating and mixing of oil and coolant.

  • Overheating: 

If the engine is running too hot, it can cause the coolant to boil, leading to steam and pressure escaping through the coolant cap.

  • Coolant Leak: 

A coolant leak somewhere in the cooling system could cause steam or smoke to escape from the coolant cap. Check for visible leaks or puddles of coolant under the vehicle.

  • Faulty Radiator Cap: 

The radiator cap is designed to maintain the pressure in the cooling system. If it’s faulty, it may not maintain the correct pressure, leading to coolant boiling at lower temperatures and escaping as steam.

  • Air in the Cooling System: 

Air pockets in the cooling system can cause overheating and result in steam escaping through the coolant cap.

If you suspect a blown head gasket, other symptoms may include:

  • White or milky oil on the dipstick.
  • Continuous overheating.
  • Bubbles in the radiator or coolant overflow tank.

Repair and Maintenance at Oceanside Motorsports

Whether you need help with maintenance or repairs around the Oceanside, CA area, the talented technicians at Oceanside Motorsports are here to help. Contact us with any questions about BMW services and more, then stop by Oceanside Motorsports for quality service today. With our Time Saver Service, we can get your car and deliver it to your doorstep once fixed. We can even help arrange to tow if needed. You can also have our loaner cars for just $10 per day while your car is serviced!

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