Q: Brakes go to floor, I hear gurgling, and white smoke comes out of tail pipe

asked by on

After I replaced the front brakes on my F-150, and lowered the truck on the jack to drive away, I saw a LOT of white smoke blowing out of my tail pipe. Nothing smells burnt when this happens - no burnt oil smell or anything else, and water drips out the tail pipe. Another problem I noticed at the same time is that the brake pedal goes all the way to the floor when I'm braking, and when it gets to the floor, I can hear gurgling or bubbling. This is coming from behind the firewall approximately where the master cylinder is located. Also, once the brake pedal reaches the floor, more white smoke is coming out the tailpipe.

I think I know exactly what is happening. Right behind your brake master cylinder is where the power brake booster is located. This booster is acted upon by engine vacuum in order to make the pedal easier to press down.

Since the booster is acted upon by engine vacuum, this means that it is connected to the intake manifold of the engine. If the rear seal in the brake master cylinder has failed, this will allow brake fluid to enter the power brake booster and would be the reason the pedal travels all the way to the floor; the rear seal is preventing any hydraulic pressure from building up in the master cylinder.

With brake fluid inside the power brake booster, the intake manifold is able to inhale the brake fluid into the engine whenever the brake pedal is depressed. This would be the cause of the white smoke. I would recommend having the brake master cylinder replaced, and having the power brake booster replaced by a certified mechanic. YourMechanic offers mobile technicians to come perform services just like this at your home or office.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Brakes go to floor, I hear gurgling, and white smoke comes out of tail pipe

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: Is it normal to hear the gears as you shift?

Hi There, This is somewhat normal to an extent to hear a slight whining of gears, especially in a vehicle with a manual transmission where the exchange of gears is dependent upon the driver. In some cases, however this may...

Q: Replaced front brake pads on bad rotors, also replaced calipers from junkyard.

Hello. From what you describe it would appear that your rear brakes may have seized up. This can be caused by a few different reasons. If your brakes were grinding and you reused the same rotor it may be possible...

Q: How Does Engine Braking Work?

Engine braking is the process of using the engine to slow the vehicle down instead of using the vehicle brakes. Engine braking can be used on both gas or diesel engines and is used to slow a vehicle down or...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
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.