Brake issue nightmare

Jlipton72

Member
Oct 7, 2015
12
0
Newton, MA USA
On my 2000 D2, I've changed all 4 calipers, Wagner thermo quiet ceramic pads, rotors, steel flex hoses, and still have a crappy pedal, I changed the booster to an 04 booster, changed the shuttle valve switch, and replaced the master cylinder with a new one, bled it with a scan tool etc, first time I went driving, all the brakes got stuck on, pulled the master and adjusted the rod, and kept doing trial and error until I got a good feeling pedal (well a tolerable pedal) Its been OK for a while, but still just not the best brake pedal, no where near the braking power in my P38, can't lock them up, even on dirt cant get it to lock a wheel and activate ABS or slide. Yesterday, out off roading, I was doing a lot of sitting spinning tires working the TC, and for a while the brake pedal completely changed, fantastic brakes, locked up on a dime on the trail, great feeling pedal, like a proper boosted brake pedal like in my pickup truck. After that the brakes got stuck on again out on the trail, pulled the master (in the woods), adjusted the rod back, drove back to my friends shop and re bled with a scan tool, now they are working but not great again, pedal has a lot of travel before it starts stopping. For the life of me I can't figure this out. It seems like the brakes are better at highway speeds and RPM, city driving, a panic stop is just not an option. The just have no bite. My father had a 03 disco that stopped like a BMW,. Any help is appreciated.

Thanks
 

leshassell

Well-known member
Sep 1, 2008
148
0
Kilgore, TX
Just curious, do you ever get any lean O2 sensor codes? I've been having the very same issues (to the point my D2 has failed inspection) and I'm beginning to think a vacuum leak is causing poor brake response but haven't had time to chase it down.
 

Rene M

Member
May 16, 2011
22
2
Houston Texas
I fought this battle for a long time. I fixed it by adding a vac reserve from Summit. I know it sounds dumb but i did not keep enough vac to have a consistent pedal. I search for a vac leak and never found one. I mounted this small vac can and my pedal has never been this good. A buddy did the same and had the same results.. My only explanation is... as the engine ages it does not produce as much vac at low engine speed. With a reserve, its consistent .
 

Jlipton72

Member
Oct 7, 2015
12
0
Newton, MA USA
I fought this battle for a long time. I fixed it by adding a vac reserve from Summit. I know it sounds dumb but i did not keep enough vac to have a consistent pedal. I search for a vac leak and never found one. I mounted this small vac can and my pedal has never been this good. A buddy did the same and had the same results.. My only explanation is... as the engine ages it does not produce as much vac at low engine speed. With a reserve, its consistent .

could you post the link to the part you used? Maybe some pictures of your setup?