Learn why carmakers use a brake booster electric vacuum pump

Most vehicles use a vacuum brake booster to provide power braking. In the past, the vacuum assist was provided by engine manifold vacuum. But all that’s changed with the newer, smaller engines, turbochargers, and EVs. In fact, EVs don’t produce any vacuum or have hydraulic power steering that could provide hydraulic pressure for a hydroboost braking system. Due to the lack of manifold vacuum, carmakers have added a brake booster electric vacuum pump to supply the needed vacuum.

Newer engines have less vacuum and EVs have no vacuum supply

The smaller engines have less displacement, so there’s less manifold vacuum available. Plus, when an engine is turbocharged or has variable valve timing, it has even less manifold vacuum available to run the brake booster. That’s why we’re seeing these vehicles coming equipped with electric vacuum pumps.

What else needs a vacuum supply?

Many emissions-related actuators, solenoids, wastegates operate from manifold vacuum. So those also need a supplemental vacuum source.

How brake booster electric vacuum pumps work

Carmakers install a  pressure sensor between the vacuum pump and the brake booster. Using the data from the pressure sensor and the brake pedal position switch, the ECM determines how much vacuum is needed to operate the vehicle’s power brakes. The ECM provides ground to the vacuum pump relay control coil ground when needed.

See this post to Learn the symptoms of a bad brake booster electric vacuum pump.

Find a high performance vacuum pump at Jegs

©, 2024 Rick Muscoplat

Posted on January 30, 2024 by Rick Muscoplat