Brake booster/system

[salesrep]

Lincoln 2011 MKX. My mechanic replaced the brake booster and now the car brakes even harder.Super hard to push on brakes and no "soft" braking at all. Something is messed up with the hydraulics. If I sit at a light too long, the engine revs and sometimes even shuts off the engine. Thoughts

 

[LazyDog]

Does it a have a check valve or one way valve and also check the vacuum hose. If everything seems fine, bring it back because it could be a defective part.

 

[meep]

This is a booster/vacuum issue. Take it back.

 

[clinebarger]

Your mechanic should have never let the car leave like that, Have him smoke the booster with a smoke machine.....I bet the seal between the Master & Booster got damaged.

 

[Astro14]

Booster isn’t working and you have vacuum leak? Take it back.

 

[supton]

Did it immediately do this, or did it start say the next day?

I'm guessing the vacuum line to the booster fell off. Maybe the clamp wasn't properly tightened, something trivial. But just go back (and drive safely).

 

[Lubener]

After shutting off the engine, you should get 3-5 "power assisted" pumps before the pedal pushes hard if the booster is working.

 

[salesrep]

Thanks, indeed the booster was defective.

 

[bdcardinal]

We have had a run of these be defective out of the box. Both Ford and Mazda ones too so there was a bad batch somewhere.