Brakes on a 94 ATX - Hard stops are nil!

[Billy P]

Greetings from Iraq. I haven't been on the board in about a year, but then I have not had much to say about the SHO world. I see we have a lot of new members. Welcome all. These guys are great and have always come through for me, I'm sure you'll find them all as helpfull as I have.

Anyway. Gang! I am coming home for two weeks R&R soon. When I left for this lovely vacation in the sun, I had just replaced the brakes on all four corners. I used the factory spec bleeding order, and I even had a helper to press the brake pedal for me while I manned the bleeding screws. Anyway, I took it out for a test drive and tried a couple of hard stops. The ABS did not do its normal pumping thing, and it took a lot of leg pressure to squeeze those brakes closed and get the car to stop. I'd guess that it takes about a 1/3 more distance to stop the car at speed than normal. I talked to the wife this morning and she drives the beast about once a week to keep the seals lubed and fluides flowing in all the right places. She said that she had to make a hard stop once and the car scared the **** outta her because it "didn't want to stop." The ABS idiot light is not a problem, so I think the ABS computer is working fine.

I am thinking I need to completely bleed the car because I may not have done such a good job the first time; or I may have abosorbed some water/moisture in the fluid.

I did a search on the forum and found some similar problems to mine. But I only have about two days to fix this thing while I am on R&R, and then its family vacation time. So I want to be sure when I tackle the problem, I have all the information I need and can get it done. Any help would be much appreciated. I don't have a lot time to spend on the internet looking things up, so I am asking for your expertise and advice.

BTW-The Forum looks great. Many improvements. I like what you have done with the place.

Later
Billy P

 

[n8rsk8r]

Hey dude, nice to hear from you! I am new, of a couple months, hang in there, and wear all your gear! I would say that it may be just that you need new fluid. go take it to a brake place and have em power purge the system, it cost like 50bucks and you can go away knowing you have good fluid. Like that car!!!! Seeen it on a couple posts, the red one of course! LOL get back in one piece and try taco bells new menu. it is great! Oh, and if you are really want response, get some braided lines, they will firm up the brake response, thanks for checking the forum!

 

[Rockledge]

If there is no binding in the pedal linkage going on, then it sounds like it might be booster-related. This can help you diagnose if it is:

Brake Booster Operation Check

1. Check the hydraulic brake system for leaks or low fluid.

2. With transaxle in PARK, stop engine and apply parking brake. Apply the brake pedal several times to exhaust all vacuum in the system.

3. With the engine turned off and all vacuum in the system exhausted, apply the brake pedal, and hold it down. Start the engine. If the vacuum system is operating, the brake pedal will tend to move downward under constant foot pressure. If no motion is felt, the vacuum booster system is not functioning.

Brake Booster

1. Remove the vacuum hose from the power brake booster. Manifold vacuum should be available at the brake booster end of the hose with the engine at idle speed and the transaxle in PARK or NEUTRAL. Ensure that all unused vacuum outlets are properly capped, hose connectors are properly secured, and vacuum hoses are in good condition. When it is established that manifold vacuum is available to the power brake booster, connect the vacuum hose to the power brake booster and repeat Step 3 (above). If no downward movement of the brake pedal is felt, replace the power brake booster.

2. Operate the engine a minimum of 10 seconds at fast idle. Stop the engine, and let the vehicle stand for 10 minutes. Then, apply the brake pedal with approximately 89N (20 lb) of force. The pedal feel (brake application) should be the same as that noted with the engine operating. If the brake pedal feels hard (no power assist), replace the check valve, then repeat the test. If brake pedal still feels hard, replace the power brake booster. If the brake pedal movement feels spongy, bleed the hydraulic system to remove air from the system. .

Check Valve

1. Remove power brake booster check valve from power brake booster and vacuum hose.

2. Blow into each port in the power brake booster check valve.

3. Air should only pass through the power brake booster check valve when blowing on the power brake booster side

Hope this helps. Take care, hope you have some real good R&R. Thanks for serving!

 

[Shoaz]

I'd second the booster idea. If the pedal is hard to press that seems to be hinting that it's a boost problem. For a street car two years is not too old for brake fluid, I don't think water absorption is the problem (I don't think it would create the symptom you're describing anyway).

 

[Billy P]

Thanks for the advice.

I'll be back in Germany in about 10 days and I'll chek the booster. I hope its something more simple. I plan to only spend one day on the car. I'll let you know if that was the problem.