So my symptoms are as follows:

Brake pedal slowly sinks to the floor at a red light. I've had a few instances where I feel like the brakes didn't engage with enough force on sudden braking. Scary.

I just re did all my pads, rotors and brake fluid. Pedal at times feels mushy too. Now my question is ...

1. How do I tell if its indeed my brake master cylinder or something else like the booster?

2. Would you buy OEM only or would you get a remanufactured one from autozone? Difference is like $120. I heard these remanufactured ones are PEZm part.

 

I know it's simple but I have to ask, you bled the system right?

 

in the FSM (Factory Service Manual) it has testing procedures to help determine if it is indeed MC or Brake Booster.

see, if you can find the scans of it online.
I do have the FSM at home, but it might take me a while to get to it, as I'm at work at the moment.

 

Booster will give a hard pedal to the point you might have to use two feet to stop. Unplug the vacuum line to the booster if you want an example but have a hand on the ebrake if you decide to take it out of park.

It sounds like the master but I don't know if the ABS actuator can cause the same symptoms or not. You can always hit ABS a few times an see if the problem changes.

I hate to ask it but are the brakes bled properly?

 

Yes .. bled to spec. I had the pedal to the floor symptoms before the tranny swap... but its just getting worse after I got my car from the tranny change. Wondering if there is anything to it.. or just coincidence.

I just topped off brake fluid twice in 3 days cuz of the brake light and VSA lights. Just ordered the master cylinder.. should arrive on wednesday. Braking force has definitely diminished. Taking it slow and easy for now.

 

There's a TSB for the ABS Modulator letting air into the system...it's expensive.

Also, there may be a fault code associated with your abs & vsa indicators...what does a OBD reader say?

 

Is it actually losing fluid?

 

I am with Matt....sounds like a VAC leak issue....

do you feel any vibrations when the issue happens?

 

I don't see any signs of brake fluid leak. Wheels and engine bay are spotless.

 

Here's a slight update/surprise: I just picked up this Fenco Rebuilt brake master cylinder from Autozone and to my surprise the cylinder itself is a genuine OEM honda part with the official logo on it. It's just replaced with new seals. Cost of part is like $47 bux opposed to $159 at dealer. I'll be installing today.

 

^Yeah, but where does Fenco source their rebuild parts from? They probably get the cheapest aftermarket stuff they can find.

 

Here's an update.. what a fuck up. As soon as I took off the front passenger side wheel off, my entire LCA and Spindle were covered in brake fluid!!

The SS line that was installed somehow was loose and was oozing fluid, causing these symptoms. Once it was tightened and the entire system was bled, brakes are back to normal.

Lesson learned. Atleast it was a cheap fix and a learning experience.