Brake Booster issue

[KingDan]

Yesterday the truck was fine, she even passed inspection. It is my DD and has 191k on the clock. Last night I was in reverse in my drive way and upon applying the brake almost nothing happen. As I was going slow I was able to stop, I went back and forth a couple times and it seemed to fix its self (hate that). This morning while driving near complete failure, I really have to muscle the truck to stop. After some research here and my FSM, I have narrowed it down to the booster or possibly the booster relief valve. My question is how likely is it the relief valve and not the entire booster. Before all of this everything was fine, stop on a dime fine. Also it is not cold here S. Texas in March 60's-near 90's. I was considering buying the valve as it is less money to start with. Anyway thanks in advance.

 

[70Cruza]

Sounds intermittent check this thread.....

97 Brake booster check valve ( tip could save your life)

 

[70Cruza]

I had brake problems and it was a bad booster, but the symptoms were just weaker brakes. Not what you described here. The thread above had specified a similar sounding problem and has a possible part # and all. Good luck brother

 

[KingDan]

Thanks, that is the thread that got me thinking, it possible could be the valve. I can stop, but it requires some serious EFFORT, that and I give myself plenty of room.

 

[DARKNESS]

Booster check valve. Same thing happened to me. It's a super easy fix, just order a new one and pop it in. I think there's a grommet for the valve you may as well replace too.

 

[KingDan]

So, so I swapped out the check valve and bushing, no dice. I guess the booster is next. I do have one question, can anyone identify the pic I uploaded, it was under the truck today, I wasn't sure if it fell off or not.

 

[Kernal]

KingDan: assuming the brake fluid is full, is the brake warning light on your instrument cluster glowing slightly?

 

[KingDan]

Fluid is full, it has never left between max and min, no light. New symptom now is I can hear a "swish" sound when I press on the brake. Also idle surge when I press the gas, I think the booster is toast.

 

[KingDan]

toast

 

[DARKNESS]

Pretty sure the idle is supposed to surge when you press on the gas

It does sound like the booster is toast. you going with a new or used one?

 

[KingDan]

Haha I meant brake. Not sure, probably go new but I need to check the prices.

 

[DARKNESS]

Ha, this just happened to me. Let me know if the booster fixes it.

 

[mdawg]

FYI... i just went through the same thing recently: hard, almost impossible (and intermittent) braking, then the eventual whooshing air sound when pressing the brake pedal. I replaced the brake booster with a refub'd one from NAPA and replaced the master cylinder with a new ADVICS/AISIN from amazon. That totally fixed the issue. The problem was really with the brake booster, though.

Just be sure to adjust the length on the brake booster rod correctly before you re-attach the master cylinder or your brake pedal travel may be out of spec.

 

[inkpot]

We have installed over half a dozen of the reman boosters from Parts Authority (used to e BAP). only had problems with one of them dying within a couple of years. I don't remember price, but it was pretty good after exchange of old unit. John

 

[KingDan]

Swapped out the booster with one from Napa, fixed the issue. The pics above I had questions about, I just discovered are brake pad pieces from my dads riding mower. Good times! Props to the site for removal and install without touching any lines! I had forgotten how hard this pig stops.

 

[70Cruza]

Good to hear!