2003 Kia Spectra 4 cyl Front Wheel Drive Automatic 70000 miles
I drove my girlfriends car last week for the 1st time in about 4 months. Her brake petal goes basically to the floor when you press it. I have checked the pads in the front and shoes in the rear. They were all in good shape along with the calipers and wheel cylinders. I have bleed the system twice times. When that did nothing I changed the master cylinder. Bleed the system twice again and still nothing. I have run out of ideas. Please help.
When you removed the MC, did you notice any brake fluid in power booster?
If you do not bench bleed the MC, you can cause the seal to rupture, because the MC is dry.
September, 30, 2009 AT 8:53 AM
I bench bleed the master cylinder before installing and then I bleed the lines after installing. The brake booster had no fluid in it when I took off the old one. The rubber hoses are in great condition along woth the hard lines. I also just double checked it this morning. Also I forgot to post that it is a non-abs car, pedal height is within spec, but free play is way too much, also the pedal to floor clearance is too low. I looked up these spec on kistechinfo. Com. Tried everything on there added my knowlege but still the same problem.
October, 1, 2009 AT 9:59 AM
If MC is good, and there are no leaks and brakes have been bled, then look at proportioning valve.
October, 1, 2009 AT 12:29 PM
I understand the how a proportioning valve might make other problems like brake lockup and such but how would it cause a low pedal?
October, 2, 2009 AT 6:30 AM
It may be leaking internally, letting brake fluid back up into fluid resiviour.
On some cars the brake pedal rod to booster, must be pointing a certain way, or you can have a low pedal, or damage the MC seal.