Brake fluid with a low boiling point should be corrected by:

Prepare for the Automotive Service Technician Period 1 exam. Study with flashcards and multiple choice questions, each question has hints and explanations. Get ready for your exam!

Brake fluid must withstand high temperatures in the braking system, and it readily absorbs moisture from the air and from the system itself. That moisture lowers the fluid’s boiling point, so under heavy braking the fluid can start to vaporize, causing a soft or spongy pedal and reduced braking effectiveness.

The correct fix is to flush the system with new brake fluid. Replacing the old, moisture-laden fluid with fresh fluid raises the overall boiling point and helps prevent vapor lock. Heating the fluid to remove moisture is unsafe and ineffective at truly removing dissolved water. Using a higher boiling point fluid without flushing leaves the existing moisture in the system, so the problem can recur. Replacing the fluid with something like synthetic oil is not compatible with brake systems and can cause serious damage.