Sc3001jzTT

iTrader: (1)

Has anyone had this happen to em?

So early today i left work and my brakes felt really touchy. so i drive down the street and as soon as i get into my neighbor hood 5 min later. my car starts to slow down really bad. i would shift gears and it would slow down and then when i tried giving it gas it would stay at a steady RPM but wouldnt go faster so i had to down shift to 1first gear. it would move fast again.

i started puling up the driveway and it barely made it. i lifted up the rear tires and i tried spinning them with ebrake off and neutral. it would not move the tires so i go try to front ones and nothing either. i disconnected the battery and pumped the pedal a few times, when i was doing that it didnt really get hard it just sank in like the master cylinder was bad. i did that and checked the right front tire and it moved freely again. i drove it out of the drive way for a test drive and everything was fine.

no abs light came on at any time while driving. So im wondering what it could be? ABS, Brake master cylinder, a relay?

Asha'man

iTrader: (1)

Very strange that you should post this, as I was just about to post a similar thread. Last weekend my gf and I went up to the mountains, and as we were heading up my brakes started locking up. I was spinning 4000 RPMs with the pedal to the floor and was at 60mph and losing speed, going up I-70 on the way out of Denver. Pulled off and stopped at a gas station and I smelled both front brakes just cooking, and my wheels were too hot to touch. I pulled out both ABS fuses in case that was a culprit, and then had no trouble doing 80mph all the way to Silverthorne. We made a few stops in Silverthorne and then headed off for Steamboat, and the car did it again a couple of times before we got to Steamboat. I was usually able to tap the brakes hard a few times and it would loosen up, and it was never as bad as it was the first time, but it's still a recurring issue. I also did not get any warning lights.

Would the car's OBDII pick up on something like this and toss a code for it?

over40driv

The only time Ive seen this is when someone put power steering fluid in the master cyl.

HeisLegend

If you can drive you car for a bit after its been off for the night and it slowly locks up on you then inspect your brake booster located behind the BMC, IIRC.

The pressure that helps give you the "feel" of your brake pedal is judged by your brake booster. They usually help give a user friendly feel. The pressure in the line isnt translated passed that little bypass valve going to the Brake booster causing it to lock your brakes The valve is most likely not the problem.

Again, try leaving it alone for the night, start her up and then drive. If it locks up as time goes, I'm almost 100 percent sure as I've gone through this before and replaced EVERYTHING prior to the brake booster.
Not a fun thing to replace, trust me.

Hope you get it figured out!

Sc3001jzTT

iTrader: (1)

Asha man, did you ever feel your brake pedal after that, that it would just be stiff at first but if your at a light and you keep pumping it it will keep sinking lower and lower til you get to the bottom? i keep revving the engine to 3 rpm slowly and i push on the brake pedal once again and it gets really stiff . brake booster? or brake master cylinder?

Mr.NA_T

both????????

Anthony85

It could be possible that the caliper has seized up as well......

Asha'man

iTrader: (1)

Didn't get to that point as I was cruising on the highway the whole time. That symptom sounds like a leaking master cylinder to me, with fluid escaping past the piston and letting the pedal go down.

P1TBLL

My sister had this happen to her RX330 about 27000 miles ago. I checked/replaced her brake pads/rotors, bled the brake lines and everything worked good. Now, 27000 plus miles later, it's doing the same thing. This time I replaced the pads only (rotors still okay) and it's still locking up. For you, the brake booster was the problem?