Brake Issue Re-Born

[SS MAYFLOAT]

I guess the old domino effect has stricken my wifes 2000 Explorer. After replacing and checking lots of the brake system, now she is claiming that sometimes when she hits the brakes they go to the floor. She will let up and step on them again and have pedal. I'm sure its probably the master cylinder. She did say that she notices it mostly when she is making a left turn more often.

I'm taking her to work in the morning so that I can check things out further. Seems like a little oil is leaking out right behind the cross member. I will jack it up in the morning a take a look at the brake line that goes to the right front. Until I crawl under it and take a look to see if there is a leak, I'm holding off on changing the master cylinder.

 

[Bondo]

Re: Brake Issue Re-Born

Ayuh,.... Sounds 'bout Right SS,....
Symptoms says Master, but a Leak needs fixin' 1st...

Good Luck, 'n don't forget the jackstands....

 

[Bob_VT]

Re: Brake Issue Re-Born

If you have a leak the system will shut down one set of brakes ie...... the front half or the back half will shut down via a shuttle valve. Check your fluid for a loss. If that is the case the shuttle NEEDS to be reset once repaired.

If your fluid is good.......... you have two other possibilities. The master cylinder or the brake booster.

A faulty ABS will also cause a "felt" loss.

 

[rbh]

Re: Brake Issue Re-Born

Look for the wet spot, you never know you may have a pin hole in the brake lines if your seeing wet.
(but the peddles not spungey is it HHMMMMM???

Maybe by passing due to wear.


Today I just replaced the vacuum pump on my 7.3 diesel ford pick up, no vacuum assist, It was a b!#ch to stop otherwise.

 

[mommicked]

Re: Brake Issue Re-Born

Could it be an air bubble, or it needs more bleeding?

 

[dolluper]

Re: Brake Issue Re-Born

Yep time to get dirty again ...at that age you should check all your lines and hoses car fully...one goes well the rest could be awaiting their turn seems to happen that way.....could be a good thing system will have all fresh fuild running through it thats the good part.....take your time do her right I know you will....any problems let us know

 

[L8-Again]

Re: Brake Issue Re-Born

Bob_VT mentioned the ABS sensor. I have seen the ABS wheel sensors go bad causing this symptom. Worked at a Ford Dealership for a few years. If it happens when turning the sensor may be losing signal telling the module that a tire is not turning, engaging the ABS. When you stop and press again, the pedal is firm. Listen for the 'growl' of the ABS and feel for the pulsing of the pedal when trying to duplicate.

If there is a leak, FIX IT before driving!

 

[SS MAYFLOAT]

Re: Brake Issue Re-Born

Got it up on "Jack Stands" .....The line I thought would be leaking looks good. Covered with oil/grease, wiped it off and very little rust. No signs of any leaks. Stood on the pedal for about 5 minuets to get fluid to leak out. Didn't find any wet spots at all. Reservoir on master cylinder is full

I have a friend that I let use my bucket truck for a few weeks. He was a ASE certified mech years ago. I called him up for a favor to help me isolate the problem and get it repaired. He is going to bring his pressure bleeder to insure all air is out of the system.

I took it out and drove around the block several times and could not get it to do it for me. Maybe it is my lead foot...

 

[SS MAYFLOAT]

Re: Brake Issue Re-Born

My mech finally showed up. We took the Explorer over to a empty parking lot. Finally got it to do what my wife was telling me. On right hand braking turns, it will not do it. On left hand braking turns, you can feel the pedal pulsate. As it pulsates, the pedal goes down with each pulse. However, wifey says it has done it several times going straight. Both front wheel sensors look good and show a pulse on an ohm meter when the wheel is spun. Wires do not have any signs of jacket tears or worn through spots. Any ideas? Thanks...no doubt this has to do with the ABS

 

[NYBo]

Re: Brake Issue Re-Born

If the vehicle has drums on the rears, make sure they are properly adjusted.

the brake booster.

A bad booster results in a hard pedal and increased brake effort.

 

[dolluper]

Re: Brake Issue Re-Born

bad caliper or slider pins seized caliper not moving in and out on pins, piston travels to far to contact rotor....or loose wheel bearings or worn....might want to do a gravity bleed also....just pull bleeder out and let it drip

 

[stackz]

Re: Brake Issue Re-Born

old broken down brake fluid particles could have formed a sludge in one of the valves inside the ABS unit for one of the wheels. very hard to pinpoint as you cant tell where the pulsating comes from. the valve probably isnt completely stuck either and just sorta sliding along whenever it catches until the hydraulic pressure overcomes it.

how many miles were put on the old fluid before you got to the issue and just started adding fluid?

If you feel confident enough, pull out the ABS unit and tear it apart and clean all the valves inside and check seals, etc. dont lose any ball bearings or springs though!

I usually grab a couple large sheets of cardboard and construct myself a "box" to work in so the springs, etc just fall around me haha.

 

[SS MAYFLOAT]

Re: Brake Issue Re-Born

I finally posted my problem on the Ford Trucks website. I was told that to find the problem, it would need to have the professional real time scan tool. I called the shop I trust to do the work on my vehicles that is beyond my capabilities. He said he did have the tool. So I dropped the Explorer off Monday evening.

Tuesday, they call me back and said that the left front wheel hub sensor ring was faulty. Had them replace the front hub. We took it back out for a real time checkout. Everything is fine now.

Thanks for the input..............SS