2CarPros - Car Questions & Answers

1987 Ford Thunderbird Repair Question


Topics covered: Brakes, Abs, Accumulator.
Mileage: 111,512 miles.

Asked on September 28, 2012

Ford thunderbird power brakes issue

I have a 1987 ford thunderbird turbo coupe, and we are currently having an issue with the power brakes kicking in when they are supposed to. The manual brakes work fine, but when it comes to the power brakes they do not kick in. This makes for a tough pedal when pressure is applied to it. We have tried to unplug the power to the brake system and that works for a while but it eventually stops working again. We just ordered an ABS control module and are hoping that it resolves the issue, but we arent sure. Does anyone have any suggestions on what it could be? Maybe a bad fuse?
Avatar Asked by Pdunkin

Answer

Replied on September 28, 2012

what is wrong? the abs doesn't work? which wold mean the abs light is on if that is the problem then you need to get it scanned to see what area is bad on the abs system. the power brakes shold work all the time, then you should check for a bad valve at pb booster, or a leaking booster.

Tiny Answered by hmac300 (expert)
17,813 answers provided
Replied on September 28, 2012

Well there is no lights that come on when we start the car up. Its just that when we are applying the brakes, the pedal is touch. We have fixed it temporarily by cutting the power to the whole system. But it just stops working again. We know that its something with the power brakes, we just dont know what it is.

Tiny Response from Pdunkin
2 questions asked
Replied on September 28, 2012

what do you mean cut thepower? power to the abs unit? you should never ever do that havea pro look at this befor eyou domore damage to the car.

Tiny Answered by hmac300 (expert)
17,813 answers provided

Replied on September 28, 2012

We unplugged the power to the braking system..

Tiny Response from Pdunkin
2 questions asked
Replied on September 28, 2012

Hi hmac300. This system gets its power assist from the hydraulic controller. It sounds like they have a stored pressure problem but that should be turning on the warning light unless the pump is just slow to charge the accumulator. My guess would be something is failing in the hydraulic control unit, and that is a REAL expensive part.

Tiny Answered by caradiodoc (expert)
17,277 answers provided
Replied on September 28, 2012

hi guys if the pedal is hard.he will need to check the vacuum at the booster hose.if the vacuum gauge is in the green.the only thing it could be a faulty booster seal.

Tiny Answered by cadieman (expert)
2,856 answers provided

Replied on September 28, 2012

Good answer, but this doesn't use a vacuum booster. The power assist comes from pressurized brake fluid, similar to the hydroboost systems that use power steering fluid. That fluid needs to get up to around 2200 psi.

Tiny Answered by caradiodoc (expert)
17,277 answers provided
Replied on September 28, 2012

i stand corrected

Tiny Answered by cadieman (expert)
2,856 answers provided
Replied on September 28, 2012

You may be seated. :)

Tiny Answered by caradiodoc (expert)
17,277 answers provided
Replied on September 29, 2012

We haven't checked all of this stuff yet. But I just reviewed new info on how I could have occurred. Apparently when my uncle was driving it, he was going up and ramp and applying the brakes. Something busted when he applied pressure to the brakes and try we're suddenly out, and no longer supplying the assistance needed to slow the car down. It still stopped, it was just tough to do with the manual brakes.

Tiny Response from Pdunkin
2 questions asked