Need to know if some has had this problem with there brakes. I did change out the brake fluid and that fixed it for about one day. After driving the car for about 1hr the brake pedal will go to the floor and the brakes will not work very good. Also in the morning after first start up what I think is the ABS makes noise and it has done this for some time but it was not till two weeks back that the brakes where not working so good and would love some info on the pedal going to the floor and I have looked and the brake fluid is still full.
-
Protip: Profile posts are public! Use Conversations to message other members privately. Everyone can see the content of a profile post.
1992 NSX Brake problem
- Thread starter badnsx
- Start date
Have you tried repplacing the brake master cylinder? I had the same problem and replaced mine and never had a problem since.
+1 replace master cylinder
You very likely have an internal leak in the master cylinder. There are O-rings that seal the internal compartments from one another. You will not find any external leaks. The fluid is simply leaking from the pressurized side of the piston needed to brake to the other side of the piston. When I bought my car the pedal was fine when cold. After a few blocks of driving though, it would then settle to the floor. A leaking master cylinder was the cause. The master cylinder on these cars gets replaced, not rebuilt to the best of my knowledge.
And as far as the noise from the ABS pump, if it only lasts 10 seconds or so after start-up it's normal. If it runs for a minute or two your ABS system needs a good cleaning or flush. Check the wiki. Lots of info on this.
Thanks for the info and I will look in to the master cylinder.
All good now Thanks
shawn110975
Suspended
yeap after you put NEW fluid in it will cause it to fail with in days. if you had left the old oil in you would still be driving the car
To clarify what I think (hope) Shawn means: It's the bleeding process that will finish off the old seals, not the composition of new fluid vs. old.
When you bleed the brakes using a full stroke of the pedal, it moves the plunger outside it's normal range of motion and can pick up debris that has accumulated in the bore of the master cylinder. This can damage the seals and cause the type of failure you saw.
If you get an older car and it's pretty obvious the brake fluid hasn't been replaced in several years (or possibly ever)...it's not a bad idea to just premptively replace the MC....espectially if you're going to do anything high-speed in the near future.
Good info here. Reviving this old thread with a follow up question. I need to replace my brake MC (pedal going to the floor after it's warmed up) and just ordered a new one. A couple years back there was a full flush of the system. Should I do another flush or remove the MC & bleed the system with Dot 3 til there is pressure back in the system? Thanks!
You are going to end up effectively doing a full flush anyway to get the air out of the system that will be introduced when you open the lines to swap master cylinders....so budget for fluid accordingly. Also, if you're just running off-the-shelf DOT 3, it might be a good opportunity to get something more resilient if you plan to do any really spirited driving.
