Hard Brake Pedal when cold

'91 Mazda 626 2.2 not turbo.

On especially cold mornings, when I first start out, the brake pedal
is hard as a brick and very high, like the vacuum assist isn't
working. It stays that way for 100 - 200 yards and two or three uses
of the brake, then it goes to normal. Vacuum connection from the
manifold seems secure. Am I gonna have to replace that whole stinking
vacuum assist unit? I hope this is not a dealer item. They will bend
me over the sink while some kid plays dueling banjoes.

Thanks for any help,

Hamish

On Sun, 30 Jan 2005 11:48:44 -0500, Hamish WAUGH <(E-Mail Removed)> wrote:

>'91 Mazda 626 2.2 not turbo.
>
>On especially cold mornings, when I first start out, the brake pedal
>is hard as a brick and very high, like the vacuum assist isn't
>working. It stays that way for 100 - 200 yards and two or three uses
>of the brake, then it goes to normal. Vacuum connection from the
>manifold seems secure. Am I gonna have to replace that whole stinking
>vacuum assist unit? I hope this is not a dealer item. They will bend
>me over the sink while some kid plays dueling banjoes.
Somewhere between your intake manifold and your vacuum assist
there should be a check valve. It's possible this valve is sticking or
not working. Start your car and after the brakes feel normal, shut off
the engine and wait about 5 minutes. Push the brake pedal without
starting the engine. If it feels hard to push, then you are losing your
vacuum that should be held in the vacuum assist chamber. I'm not
sure about your particular model, but try squeezing the hose that goes
from the intake to the brake chamber. If you find a hard spot in it like
a lump, that is your check valve.
John