Brake pedal becomes extremely stiff overnight

[Fire0nic3FX]

Nope they aren't keeping my car. They told me to bring it back once the part comes in.


I do have some good news though. The check valve hose came in earlier than expected and I dropped the FX off this morning and got another loaner. By lunch time they finished the car. I'm going to pick the FX up first thing in the morning.

They said if this doesn't fix this issue next they will replace the brake booster. I hope not!!! They said that's a big job and a lot of things will have to be taken apart. Let's hope this check valve replacement fixes this issue!!


You guys know me one thing I don't like is seeing my FX taken apart.
Sent from my SPH-L720

 

[ryus]

Nope they aren't keeping my car. They told me to bring it back once the part comes in.


I do have some good news though. The check valve hose came in earlier than expected and I dropped the FX off this morning and got another loaner. By lunch time they finished the car. I'm going to pick the FX up first thing in the morning.

They said if this doesn't fix this issue next they will replace the brake booster. I hope not!!! They said that's a big job and a lot of things will have to be taken apart. Let's hope this check valve replacement fixes this issue!!


You guys know me one thing I don't like is seeing my FX taken apart.
Sent from my SPH-L720

Do you have any updates as to whether the replacement hose with the check valve fixed the problem? Or could it have been due to the cold weather, as long as your brakes don't lose vacuum while the engine is running then there shouldnt be any issues.

I'm not so sure if the brake booster is supposed to keep the vacuum indefinitely after you turn off the engine, since the other end is connected to the intake manifold and at that end it doesnt mean its air tight is it?

 

[Fire0nic3FX]

update

They replaced the hose. I go out to start it in the morning and could barely press the brake pedal down again to start it. And now now I hear this moaning noise from the brake booster area.

Guess its back to the dealer to change the brake booster

Anyone know what has to be done to remove that?

Sent from my SM-T217S

 

[Exotich]

Mine is usually stiff when I get up in the morning too, oops, you were talking about the car, sorry.

Seriously though, I have never noticed the pedal being stiff, when I start the car I barely touch the pedal, just enough for the push start button to work.

Grandpa Wayne is doing his thing. My friend had this problem on his G37 it was a faulty break pad that caused overheating of brake fluid. Keep us updated on the booster.

 

[ryus]

update

They replaced the hose. I go out to start it in the morning and could barely press the brake pedal down again to start it. And now now I hear this moaning noise from the brake booster area.

Guess its back to the dealer to change the brake booster

Anyone know what has to be done to remove that?

Sent from my SM-T217S

I don't think you had a problem to begin with, just because the brake booster loses vacuum overnight doesn't necessarily mean there is a vacuum leak. I havent found definitively if vacuum is supposed to remain after turning off the engine. Vacuum may not stay due to colder temps and non sealed system.

If you had a leak, you would notice your brake pedal feel while the engine is on to be alot harder than normal and should be all the time, not intermittent. Also a leak in the vacuum would affect the engine rpm stability from what I have read.

 

[shadow191]

Well, the check valve is there for a reason. And I've never had an issue with pressing the brake pedal before pushing the start button on various cars, even after sitting for weeks. I don't think the diagnosis was vacuum leak, it was a bad check valve which caused vacuum leak while the car was sitting. It's a one way valve so while the car is on and in vacuum, no issues. And FWIW, a vacuum leak will cause rpm to fluctuate, your brakes can also feel weak since the booster operates on vacuum.

---------- Post added at 10:24 AM ---------- Previous post was at 10:22 AM ----------

That's unfortunate. I've never taken the FX brake booster out, but if you look, it's connected to the hard lines going to your brake lines. Those all come off before you can remove the brake booster. And it can be messy since they're opening the brake system.

update

They replaced the hose. I go out to start it in the morning and could barely press the brake pedal down again to start it. And now now I hear this moaning noise from the brake booster area.

Guess its back to the dealer to change the brake booster

Anyone know what has to be done to remove that?

Sent from my SM-T217S

 

[2009FX50S]

Hate to bring up a very old post but my 2009 FX50 just started experiencing this issue. Brakes seem to work fine but in the mornings when I start the car I can barely depress the brake pedal. Were you able to get this resolved?

Thanks