Brake pedal looses pressure the longer you hold it

[Ollie16v]

Hello again folks. Seems I only post here when I need something...but that's what you get for being so helpful

The daily is giving me grief again (probably time to get rid of it), the brake pedal is loosing pressure the longer its pressed for. So for example during a long slow stop it starts slowing the car fine, but then when you expect it to bite and actually stop the car, there's nothing left! Nearly gone out into roundabouts a few times now.

I bled the brakes so there is brand new fluid in there and have kept an eye on the level, it's definitely not loosing fluid. The front disks and pads also have plenty of life.

The only thing I haven't checked yet is the rear drums....if they are worn out, could that be the cause?

Thanks in advance!

 

[richwilkins50]

Hello again folks. Seems I only post here when I need something...but that's what you get for being so helpful

The daily is giving me grief again (probably time to get rid of it), the brake pedal is loosing pressure the longer its pressed for. So for example during a long slow stop it starts slowing the car fine, but then when you expect it to bite and actually stop the car, there's nothing left! Nearly gone out into roundabouts a few times now.

I bled the brakes so there is brand new fluid in there and have kept an eye on the level, it's definitely not loosing fluid. The front disks and pads also have plenty of life.

The only thing I haven't checked yet is the rear drums....if they are worn out, could that be the cause?

Thanks in advance!

maybe faulty brake servo?

 

[Dan@SJM]

Master cyl.

 

[Ollie16v]

Are either of those quick and or cheap to replace? Are there any indications that I can look for? Which would be the path of least resistance?

Thanks again!