Car will not stop.

[BM3MW]

So Guys my breaks are not working that well. If im sitting at a stop light after a few sec. the break pedal sinks in to the floor and i have to push the break pedal harder to keep the car from rolling. Also if im driving at speed and come up to a red light the same thing happens to the peddal at first it breaks crisp and fine, but after a sec. or 2 the pedal sinks in and breaking is not very crisp and strong. So i have to step on the pedal hard to get the car stopped. If i pump the breaks it seems to break fine or better. Is this my break booster going bad or what? IF anyone knows whats going on let me know please. Instructions on how to fix this or diagrams of it would be amazing. Thanks in advance.

[willwren]

BRAKES. Not Breaks.

You either have air or water in the system. I suggest a full FLUSH bleed. The entire system with new fluid. Brake fluid doesn't compress, which is why it can do the work for you. Air and water compress, wasting part of your pedal travel.

[00Beast]

Sounds very much like a master cylinder with a bad seal.

[willwren]

The pedal sinking to the floor at a stop is a clear indication of moisture or air in the system. While the master cylinder is a possibility, the only way to prove it other than removing it is to bleed/flush the system. This is why I suggested it as a first troubleshooting step.

[renchjeep]

My 94 SE was doing the same thing. It was the master cylinder bypassing internally. Try holding MORE pressure on the brake pedal idling in drive.....then release a bit. The sinking pedal at that point indicates internal bypass, and a NEW, not rebuilt master cylinder is in your future. ASAP.

I have had bad luck with rebuilt m/c's many times in the past. Maybe things are different now. Not sure.

Some people will tell you not to buy a new m/c from Autozone, but I bought one, properly bench-bled it, and refilled the entire system with Prestone Synthetic DOT3 fluid, and have never been happier with my braking.

IIRC, it was 49.99 for the new Autozone m/c, with a lifetime warranty.

Whatever you decide to do, make sure to COMPLETELY flush the old brake fluid from the system. Brake fluid (especially OLD brake fluid) is hygroscopic (spelling?), meaning that it sucks up moisture from the atmosphere. You DO NOT want water in your braking system! That can cause all kinds of problems, like internal rusting of your wheel cylinders and calipers. Internal rust in the cylinders/calipers WILL take out the rubber seals. High temp boiling of the water in the fluid causes excessive "brake fade" as well.

Oh, if you have ABS, which I assume you do, bleed each wheel with the key in the OFF position. Do not use the ABS pump to bleed the system.

I am sure others have opinions here, and please listen to them as well. I am only speaking from personal experience, after all.

Good luck, and let us know what your results are.

Sorry for the rambling.....

[renchjeep]

P.S. Willwren, when will people learn the difference between "braking" and "breaking"? No offense to anyone, but a little spelling goes a long way........no that I ahve ever seplled anyhtingh wrogn!

[BM3MW]

haha sorry guys for the misspelling i was in a rush at the time. Anyhow back to buisness. Where is the Brake M/C located? When doing a complete Flush what are the steps? Ive Bled the brakes on my old bmw, dont know if its the same? start at the (1)passenger rear, (2)drivers rear, (3) passenger front, (4) drivers Front? How do you know when all the old brake Fluid is out? Are there different Color Brake fluids for this car? Any Steps that i should know when Replacing The Brake M/C? Thanks Guys i have not done much work on these cars dont know where everything is located etc. Also How fast is a stock 94 SSEI 0 to 60? Of course taking into account very Old age..

[00Beast]

Master Cylinder is located on the firewall, right ahead of where the pedal is. Pop the hood and it's right there.

As far as bleeding, your order is correct. You want it so that clear, new looking fluid is coming out at all 4 corners. Suck as much out of the master cylinder as possible with a turkey baster or similar, fill with fresh DOT 3 or 4 fluid, then go from there. Do NOT use DOT 5. It will wreck the system.

[BM3MW]

Okay I Got a new M/C and brake Fluid. Had one question tho. The new MC did not come with any Seals or O rings of any kind. Before i start doing this job i would like to know if there are any or do i just install metal to metal?

[willwren]

You should have gotten two plastic fittings and a hose to bench-bleed the unit first. That needs to be done before install. The only seals are for the reservior, and they should be pre-installed, and you should have 2 pins provided to lock it in place. Otherwise, the two brake lines are metal to metal compression fittings.

If you haven't bench-bled a MC before, speak up. It needs to be done correctly, then you'll have to bleed the whole car after install also.

[BM3MW]

So I did the job. everything seems to be working just fine now. Thanks so much for all of your time. the old brake fulid was black in color and very dirty.

[00Beast]

Glad we could help. This is a great reminder to everyone that brake fluid absorbs water and needs to be flushed regularly.

[renchjeep]

So, how quick is a 94 SSEi 0-60?

[00Beast]

Well considering a stock 00+ is rated at 7.3 seconds or so, and they're lighter with a smidge less power but more low end torque, I'd say it's right in that area.