Re: Power-assist brake pedal "collapses" to manual level on 89 corolla.



On Tue, 18 Sep 2007 01:06:34 GMT, "Jeff Strickland"
<crwlr@xxxxxxxxxxx> wrote:
Thanks for your quick reply, Jeff. I really appreciate it.

At the very least, you have emptied all fot he brake fluid and need to
refill the reservior.

Checking the brake fluid was the very first thing I did when the
brakes started to go "soft". The brake fluid level is just a hair
below the "full" line. So that is not the problem.

Assuming (a very UNSAFE assumption) that is all you
need, you will need to bleed the brakes until all of the air has been
removed. Having said that, if the reserviors are empty, you will need to
Bench Bleed the master cylinder before you can st art doing anything else.

If all of the brake fluid is gone, then you have a leak somewhere that needs
to be fixed first.

As I said above, the fluid is fine.

MY guess is that there is a vacuum leak somewhere; either in a line or
in the diaphragm in the power assist unit. The next thing I will check
is a possible leak in the vacuum line. Although I don't know if it
would be loud enough for me to hear it. I suspect it would be if it
were big enough to disable the power-assist unit. If the vacuum leak
were THAT BIG, I assume that it would really be affecting the
performance of the engine, which is running just fine. So I wouldn't
expect that to be the problem.

Have you got any other ideas as to what it might be?


Since you said the service lamp is lit all of the time, and asked for an
online manual, I conclude that you should be paying for this service. You
should at least find a friend or co-worker that knows how to do this kind of
thing.

Getting a car to go fast is no trick at all, getting it to stop is another
matter. If it fails to do 60 in a quarter mile, nothing is lost but your
pride. If it takes a city block to stop from 60, lives are at stake.

You are absolutely right on that. I have no intention of driving the
car any further until the problem is solved.

Sincerely, BlackHawk






"BlackHawk 96" <blackhawk96@xxxxxxxxxxxxxxxx> wrote in message
news:5t6ue3lrqudnm2n73tjlitjn017u4rmu49@xxxxxxxxxx
I was hoping that some kind soul might be willing to give me a little
assistance with diagnosing this problem. While I was driving home,
when I applied the brakes, the pedal slowly sank like the air was
being let out of a balloon. Every time I applied the brakes, the
"sinking" was a little faster, until there was no deflating feeling at
all. The pedal just went straight through the power assist, down to
manual brakes. The "brake service warning light" is on all the time.
Any help at all will be greatly appreciated. A reference to an online
service manual would be great.

Sincerely, BlackHawk

.



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