I want to drive my exploder, but afraid I won't stop

[pemz0r]

I want to say that I am very mechanically inclined but I am stumped.

I have a 1995 Ford Explorer with 160k miles and today the brakes "sorta" went out. When I first press the brake pedal the car starts to stop normally, but when I lift my foot off the pedal and press it down again it becomes spongy. If I keep repeating this process the pedal will hit the bottom of the floor and vehicle will barley stop. I am thinking it's a bad master cylinder.....

Does any one have any ideas?

Thanks,
Cameron

 

[DaExplorer]

Did you check for leaks, and fluid level? Had you been doing a lot of braking like down hill? If the brakes overheat they can feal like that. Start by being parked somewhere level and put your foot on the brake pedal and push down and hold it for a while and see what happens (don't pump it). If it continues to fall then start looking for leaks. Check the front brake lines , the rubber ones in the wheelwell. Anyway that is where in would start looking. Keep us posted.

 

[pemz0r]

Brake Fluid is correct.

I just held the pedal for 20 seconds, and the pedal doesn't move and it feels great.

But has soon as I decompress the pedal and put pressure back on, it starts to fade. Also, when I "pump it" there is like a hissing sound, almost like the pedal is leaking air.....

Any ideas?

 

[my98nnj]

If the brake pedal falls your losing pressure somewhere. Check for fluid leaks, binding caliper guide pins, and the master cylinder.

 

[boominXplorer]

I would look for leaks down EVERY brake line down the frame and to each wheel. The hissing you are talking about is the booster. If you can not find a leak in the system you need to look into the master cyl and the booster (big round thing behind it) It should make a light hiss noise when the brake is applied but shouldn't be noticeable. You can get you a new master cyl / booster setup for about $150-$200 at a local parts store.

Also... Have you done any recent brake work or had any done?

 

[pemz0r]

I haven't done any brake work, but I did get new tires 3 or 4 weeks ago.

 

[benjamin222]

i had that problem on my windstar or freestar can't remember wich, anyways it was a seized caliper

 

[koda2000]

if there are no leaks anywhere it sounds like your master cylinder is shot. you shouldn't be hearing any hissing coming from the brake booster, so it may also be shot too, but a bad booster will not cause a spongy pedal, or a pedal that goes t the floor. only a "hard" pedal (as in no power assist). you can buy a reman booster with a master cylinder attached for about $200-$250. please don't drive the vehicle the way it is.

 

[pemz0r]

Since the master cylinder was only $40 from Pep boys, I decided to give it a chance. I switch it out and it works perfectly.

Thanks Everyone!!!!