I have a 77 targa and I am experiencing brake pedal fade. When the pedal is depressed it usually is high and very firm. Lately it has begun to intermittently show fade where the pedal goes 3/4 of the way to the floor. When I pump it, it has always come back to the normal position.

Last week I had the brake fluid system flushed and changed and I had hoped that this would take care of the situation. I thought there may have been some air in the line. I have not noticed any leaks but I also know that all of the brake lines are original. What could be the possible problems?

Thanks

 

It sounds like you may have a bad master cylinder. Do you know if it has ever been replaced?

There are seals in the master cylinder that will go bad over time. Brake fluid (under pressure) will leak around the seals and you will get a soft pedal. Pumping the brake will bring back a firm pedal...briefly, then it goes soft again.

Bruce

 

If you press on the brake pedal hard, and it slowly goes towards the floor, that's new master cylinder time. Bruce described why that happens.

 

The guys have it right - master cylinder. Unfortunately, although the car should be fitted with a brake system warning light for some reason this sort of fault is not picked up - I guess its because the warning system is only for major failure where the system pressure is non existant. While your at it get the flexi's changed too!

pjc

 

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"><strong> While your at it get the flexi's changed too!</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">If you're referring to the rubber brake hoses, these should be replaced roughly every 10 years. If you don't know when they were last replaced, safety would suggest replacing them at the next available time.....like when swapping the master cylinder, as PJC suggested.