NeGraVity40

Hey there! I'm going to give a small summation as to the situation I have with my brake system and hopefully someone has some ideas! I started building a 4th gen 92 prelude SI as a track/rallyX car. Brake pedal had always felt normal when it was just a daily driver until the last few months and it began to feel soft. I went to put on track pads, drilled/slotted rotors, and all 4 new calipers and when on a test drive the brake pedal still felt the same. Later that week I replaced all brake lines with steel braided lines and suddenly the pedal would be soft and sink to the floor. No more air is coming out when bleeding so I suspected a faulty master cylinder. Bench bled the new reman master, installed it, and bled the system. The pedal felt roughly 5% better. The pedal is somewhat squishy and always feels good at first and then slowly sinks until it hits the floor whether driving or at a stop.

There are no leaks, all calipers are new, master was replaced with a reman, and the only thing I have not touched is the ABS unit. The car is fully stripped out and has an ABS unit under the hood but the ABS control module is removed. Could the ABS unit be suspect (aka have air trapped inside) or possibly the the reman master may be a faulty replacement and I should try a new one? Is there a special way to bleed the ABS unit (I have tried opening the bleeder on it to bleed it with no avail and have heard I may need a special computer/scanner) or eliminate it altogether? Please help lol!

spray004

It's definitely air in the lines. Some cars are a pain to bleed (my F150 is a pain), others are easier.

NeGraVity40

I have tried bleeding it, driving it for a while, bleeding it, driving it, and so on a few times and only get pure, clean fluid with no air. I have been using the proper RR, RF, LR, LF (I can't remember the exact procedure so sorry if this is inaccurate) procedure too. I'm not sure what else to try.

motoxxxman

I've had this problem before, it's almost definitely air in the ABS unit. loosening the bleeder on the abs unit probably introduced more air too. the only way to bleed it is to have it be functional and hammer down on the brakes on a slippery surface to activate it, it's a self bleeding system for the most part. or you can have a dealer bleed it, which requires a special computer, and it has to be functional for that too.

I vote you just remove it and install an oem proportioning valve. eliminate any future issues. you obviously dont want the abs for racing, so might as well look at it as weight reduction too.

NeGraVity40

I had a feeling this would be the case. Thanks for your help! I have another question then. Where can I find an OEM proportioning valve so I can just eliminate the ABS Unit altogether?

NeGraVity40

Actually just found one on Amazon.com for about $167 with no picture; however; it says it is compatible for the 92. Is there anywhere else you would recommend looking other than the dealer?

motoxxxman

preludepower.com or any of the prelude facebook groups. used is perfectly acceptable

snobordboy

Keep in mind, all of your brake lines will be different as well for the front of the car, as well as a different master cylinder.

If you can find a 92-95 S model, with the single cam engine, they did not have ABS from the factory, so they have the correct prop valve and lines to delete ABS. I removed the whole system from a used car, and it works perfect, all factory parts.

You can bend new custom lines, but you still need a prop valve with the correct split, and the right master cylinder.

NeGraVity40

Ah thanks for the help guys! Much appreciated!

KILLluminati410

I'm having a problem with my recently purchased 97 prelude. I just installed new rotors and pads plus rear calipers since driverside rear seems like it hasn't worked in years and passenger side piston would not retract to put new pads in.
I installed everything and still can't get my driverside caliper to work and now I have a leak right by the firewall (please see pics). if anyone can help please email me at hondatic410@hotmail.com