Skip the auto shop - Our mechanics make house calls

Q: Where is the vacuum check valve located on a vacuum assisted brake booster?

asked by on

Good afternoon, my name is John and I am replacing my power brake booster in my 2007 Lincoln MKX. Was told I need to disconnect the vacuum check valve but I'm not sure where it is located. I have diagrams and what not, but none of them actually say a vacuum check valve. The paperwork I have states that the brake booster check valve must be disconnected from the brake booster prior to removing the master cylinder or the master cylinder seal may be drawn into the brake booster. By chance is the vacuum check valve located with the manifold vacuum hose assembly on the backside of the power brake booster?

My car has 178000 miles.
My car has an automatic transmission.

The check valve is built into the hose that connects to the brake booster. The hose should be disconnected from the booster connection when removing the master cylinder. If you apply vacuum to the hose after you remove it from the booster, you should be able to hold vacuum on the line indicating check valve is good. If it will not hold vacuum, then you will need to replace the line assembly with check valve built into it. If you need help with this repair, YourMechanic offers a repair and diagnosis service preformed by a certified mechanic that will commute to your location to help you replace your brake booster vacuum pump.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  • Home
  • Questions
  • Where is the vacuum check valve located on a vacuum assisted brake booster?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Drove with parking break on

Hi. Driving with the parking brake engaged can cause some problems that may not automatically pop up. First and foremost, to answer your question if it's even possible the answer is; it depends on the car. Some cars have a...

Q: My 4WD is not engaging. Is a 2007 Silverado have electronically controlled axle actuator or vacuum? Or is my problem in the hubs?

Hi there. The actuator on your 4WD system to your vehicle is electronic. Most of the Silverado 2500 model Chevrolet trucks have issues with the actuator failing in the front axle due to weather and road conditions. Check the harness...

Q: Clunk sound when I set on reverse and when I let go of gas pedal. Rattle noise has been increasing over bumps.

Hi there. Sounds like one or both CV Shafts are loose and are moving when you put the transmission in gear. Plus the squeaking noise is from the disk brakes system on the front as they are being forced to...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.