Brakes dead at cold start

Since January I have had to engage the e-brake so my MINI does not roll after cold start up.

When I push hard on brake, it slowly depresses and the car rolls back (or forward) for a few seconds - until the brake finally takes.

What is this? And who else has had it?

ty

 

I have the same problem. It showed up a few weeks ago. It's either:

1. Bad check valve on the vacuum line leading to the brake booster
2. Bad diaphragm in the brake booster.

Problem #1 is a mere inconvenience.

Problem #2 could be disasterous. If the diaphragm is torn, it could decide to rip some more and affect the brake booster's performance even when the engine is running.

I haven't took mine in for repair yet, and I haven't (yet) isolated which problem I have. Mine is an 05 built in late Feb 2005. When was yours built?

Rawhyde

PS PM me if you want to hash this around some

 

Mine's a May 04 build. Such a nuisance I wish I had mentioned it last dealership visit. But then, it would take a five hour sit on a cold day to replicate. Maybe it happens more when the car is parked on a grade - then that could just be when i notice it. I'm opting for #2 because there have been times whan the pedal has resisted strongly when operating the vehicle.

 

Rawhide sounds dead-on in his analysis. Don't screw around with this one. It could get a lot worse real fast at the wrong time. Take it in to the dealer and leave it overnight (if you can).

 

When I first noticed the problem a few weeks ago, my vacuum would bleed off overnight or from the time I arrived at work until lunchtime.

As of last week, it'll bleed off in the amount of time it takes to duck into a convenoence store and get a Coke.

How long does yours take to bleed off? Has this time interval been constant, or has it gotten to the point that it happens more quickly?

Rawhyde

 

i'm convinced this needs professional attention. i'd say it takes about 4+ hours to lose vacuum. i've only noticed it consistently at work, parked on a decline.