1996 Taurus master cylinder

I have a 96 Taurus 3.0v6.I replaced the master cylinder last month because the pedal was dropping to the floor.I bled the system well,and everything seemed to be working well.Now I apply the brakes and one minute it goes to the floor,the next I get what seems like a full application even if ive just gently stepped on the pedal.It is like the abs is kicking in as the brakes vibrate and carry on like a Mariochi Band on slippery surfaces.Ive rebled the system,and checked for leaks anywhere ,and found nothing.Also,if I am at a light with the brakes on,I can sometimes feel the pedal start to sag again.whats the deal here?Is it something in the abs,or is there something additional I must do when working on a car with abs?Any help would be appreciated.Patrick

I would say your new master cylinder is defective. Was it new or rebuilt? The part about it suddenly going to the floor shouldn't happen. The part about sagging at a stop light seems to be normal for this vintage of Ford vehicles. Anyway as I see it, you got a defective replacement master cylinder.

I would say your new master cylinder is defective. Was it new or rebuilt? The part about it suddenly going to the floor shouldn't happen. The part about sagging at a stop light seems to be normal for this vintage of Ford vehicles. Anyway as I see it, you got a defective replacement master cylinder.

thank you mechhound,I was kinda thinking the same thing.Oh and by the way ,it was a rebuilt mastercylinder from NAPA.The clincher now will be because I cant locate the reciept,will they honor an exchange afterall.Im hoping so as Ive bought alot of parts from them.thanks again for your help

thank you mechhound,I was kinda thinking the same thing.Oh and by the way ,it was a rebuilt mastercylinder from NAPA.The clincher now will be because I cant locate the reciept,will they honor an exchange afterall.Im hoping so as Ive bought alot of parts from them.thanks again for your help

I wouldn't think not having the receipt would be a problem. Most places like that use electronic bookkeeping now days. Especially beings you do a lot of business with them.

should be no problem with return but get a new one they are/were $5 more
when i replaced one over the summer

and bleed it before you install it!!!!

well I called them today and they said no worries,bring the old one back and switcheroo will happen.Ill keep you updated on my progress if interested.