Crazy!?! Brake Problem???

[TsiBoosted4g63]

Hers the story....I am driving down the highway (yesterday) and all the sudden i feel my car start to stop like i was hitting the brakes. My brake pedal all the sudden felt like a rock and wouldnt push down at all not even a little bit. I tried reving it up really high to see if the car would move. It moved barely and then wouldnt move at all. I was actually able to get over on the shoulder and i was on a slant somewhat and the car was in neutral and wouldnt roll at all. I let it sit for a little bit and i started it back up and I was able to move it a little more it wasnt stuck anymore. I didnt want to rick anything so i just got it towed back to my house. A little bit ago i went out to check it out, i decided to start it up and it moved fine and the pedal seemed normal again. If i put it in neutral i could push it as well. I have no idea what this could be but i think its crazy. Please give me your opinions about this. Thanks

 

[Morphius]

ok. If the check valve is bad in the vac line what would it do? Or how will ii know if its bad?

The booster is vacuum assist. If the valve was bad, the pedal would simply act like you killed the engine. I'd check it by popping it off and try blowing/sucking through the valve.

 

[TsiBoosted4g63]

The booster is vacuum assist. If the valve was bad, the pedal would simply act like you killed the engine. I'd check it by popping it off and try blowing/sucking through the valve.

i checked the valve i could only blow through one side and suck air through the other...So i guess thats eliminated

 

[Morphius]

i checked the valve i could only blow through one side and suck air through the other...So i guess thats eliminated

Sounds normal.

Regarding your t-case. Have noticed it leaking?

 

[TsiBoosted4g63]

Sounds normal.

Regarding your t-case. Have noticed it leaking?

Not that i know of. Jack is in another car that isnt here right now so i am going to check that as soon as i can ...i will drain the fluid as well to make sure its normal

proportioning valve is next...what can i do to make sure that is/is not the problem?

As others suggested first, I'd strongly suggest with inspecting your front brake calipers first. Sounds like your pass side is for sure bad given it "smoked". I'd get that fixed first. I think you might have a combination of issues and you need to start with the calipers.

I do find it odd that all four wheels don't move. Did you have all four wheels in the air when you checked?

yes i jacked up one wheel at a time and i think only one moved the slightest bit but they were all not normal and were still rubbing on the pads

Proportioning valve can cause that. It won't allow the fluid to go back into the master cylinder. Try breaking the lines loose at the valve and see if you can get any air or fluid out. Then see if the pedal feel changes.

couldn't air get in the lines? You are saying crack each bolt loose on there?

I also just talked to a mechanic that supposeably knows about brakes. I explained the issue and he said if there is vacuum to the booster and its not working then the booster is most likely bad. He said that if it was the proportioning valve the brake pedal would be soft and it would act as if there were no brakes at all. Does this sound accurate?

why has no one mentioned the brake master cylinder yet?

maybe this can help a little. Today i went out to start on the car/brake problem or whatever it is and the pedal wasnt hard anymore and the brakes werent locked up. This happend the first dat it happened then it went back to being stuck again along with the pedal being hard. Does this sound like a master cylinder?

 

[TsiBoosted4g63]

Resolved

 

[Morphius]

Resolved

For the benefit of others here, can you post anything else you found and what you did to resolve the issue?

 

[TsiBoosted4g63]

For the benefit of others here, can you post anything else you found and what you did to resolve the issue?

Honestly I am still confused. This is what I did....I took the brake master cylinder off and noticed that the rod coming out of the booster was sticking out to far and it was putting pressure on the master cylinder...So I was thinking how I could somehow make the rod go back in. I took the linkage off of the brake pedal and on the firewall another rod comes out. I pushed the pedal all the way to the floor causing the rod to fully extend out of the M/C and held it there with vice grips. Then i out the linkage back on the pedal and adjusted it from there. This is what i think i did...I made the rod coming out of the booster go back in more so that there wasnt any pressure on the M/C. Then I bled each caliper. After that I saw that my right rear caliper was missing the upper bolt. So i replaced that since there wasnt even one there. Now the pedal just seems like it is soft and I have to push the pedal all the way down to stop. So I think i now just have to adjust the rod by the firewall so that the pedal doesn't have as much slack.

 

[Morphius]

Honestly I am still confused. This is what I did....I took the brake master cylinder off and noticed that the rod coming out of the booster was sticking out to far and it was putting pressure on the master cylinder...So I was thinking how I could somehow make the rod go back in. I took the linkage off of the brake pedal and on the firewall another rod comes out. I pushed the pedal all the way to the floor causing the rod to fully extend out of the M/C and held it there with vice grips. Then i out the linkage back on the pedal and adjusted it from there. This is what i think i did...I made the rod coming out of the booster go back in more so that there wasnt any pressure on the M/C. Then I bled each caliper. After that I saw that my right rear caliper was missing the upper bolt. So i replaced that since there wasnt even one there. Now the pedal just seems like it is soft and I have to push the pedal all the way down to stop. So I think i now just have to adjust the rod by the firewall so that the pedal doesn't have as much slack.

Ok, so it sounds like the brake pedal was misadjusted. Did you readjust it and rebleed your brakes? It also sounds like you have air in the lines if it's "soft".

 

[bmoha2]

I have had similar experiences in the past. U need to take a closer look at each caliper. And by closer look I mean... Take the caliper off, inspect the caliper slider bolts to see if they are corroded or lubed or bent or in your case missing. The caliper should slide easily back and forth ont hese slider bolts if not replace them. They are cheap to replace. Lube them with brake specific silicon lube. Check the brake pads themselves to see if they freely move in the brass retainer clips. I have had to grind every single set of EBC brake pads that I have put on the car. If the clips are bent or not in good shape replace them. Inspect the calipers themselves. Make sure the seals are intake. Then press down on the piston itself. You should be able to press a piston in by hand especially on the front calipers. One piston will slide in and the other will slide out. If they don't it's time for a rebuild or replacement. This can also be done with the rear calipers just make sure you pop the cap off the top of the brake reservoir. Inspect your soft rubber brake lines from the brake caliper to the hard they don't look to be in good shape...hard brittle or cracking replace them. The stock one way check valve from the intake manifold to the brake booster is really not a piece of high performance equipment. Some people myself included have discarded it and gone with something higher performance. The stock check valve doesn't like high boost or oil or high temperatures. It can be defeated fairly easily and when it does it blows up and pressurizes the brake booster and creates a hard pedal and applies the brakes. I had that exact problem. That causes things to get hot. So if you let the car sit for a bit and cool off and let the pressure bleed off your brakes will work again as you stated. I replaced the stock one way check valve with one that is good to 300 psi of pressure, is good to 300 degrees and isn't bothered by oil. It is brass with stainless steel spring and piston. I think I got mine from Brake Mcmaster scher. There is a link on here about it. I replaced it and have not had a problem since. In my experience with our cars a sticking brake caliper causes a spongy feel at the brake pedal not hard.