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Need Help with a Diagnosis. Soft depressing brake pedal

10 December 2010
Hey Guys
So a few weeks ago I bought a 91 Berlina with 72k miles on it. Over the weekend I decided to take a roadtrip with the gf from NJ to Boston, over 250 miles one way. The car drove perfectly, not a single hiccup until sunday afternoon. Pulled the car out of the garage and started cruising around Quincy Market for about 30-40 minutes. Thats when the pedal started to get more and more soft. When I was completely stopped, I would then notice the brake pedal to start sinking towards the floor. :confused: The more I drove around, the softer the pedal got and the less braking power I had.

At this time I called the towing company and in my mind I was going to have to tow the car to a no name garage and then spend another night at a hotel in Boston ... The tow truck tells me it will take 30 minutes for him to get here. I'm parked on the side of the road, I check my brake fluid levels, its topped off, and no leaks anywhere. I get back in the car and I fully depress the brake pedal a few times. I let the car sit for about 20 minutes and when I started the car back up, the brake pedal felt fine again, so I drive around for a few minutes and it was still ok.

I then decided to try and make the 4+ hour drive home and thank god I made it! The brakes felt fine the entire drive home. Now what do you guys think is the problem? Simple nsxprime search points towards Master Brake cylinder.

Is that all I need to replace?

Best Regards
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You are 100% correct. Those are the typical symptoms of a bad master cylinder. There a few Acura dealerships where you can buy one online or call the parts department and get a 20% discount. You can try Delray Acura's webiste, or call Acura of Augusta. It's an easy DIY.

I don't have any experience with aftermarket fuel pumps, sorry I can't help you there.
Thank you guys for the input. Much appreciated. Just wanted the confirmation before I go out and buy the parts.
If you are doing a master, you may want to consider upgrading your pads.
There are some aftermarket brake pads that will really enhance braking. I switched to the project Mu's. Very nice stopping, no fading under spirited driving. My stock pads began to fade after about 20 minutes of mountain driving.

There are plenty of threads on brake upgrades.