I’m having the same problem as the OP except I have removed my ABS already. i was sooo hoping for a solution in here. And replacing the brake booster just to see if it is bad is not an option. That thing is nightmare to re and re.
It says a lot though that I am having the exact same problem but I have ALREADY deleted my ABS. Which means? Your problem most likely does not have anything to do with your ABS components working properly. WTF could this be?
Hey Marc, how goes? You mentioned rotor “run out” and “kick back”, care to elaborate on this a little for us laymen? 
[QUOTE=Zenmachine;2220400]It says a lot though that I am having the exact same problem but I have ALREADY deleted my ABS. Which means? Your problem most likely does not have anything to do with your ABS components working properly. WTF could this be?
Hey Marc, how goes? You mentioned rotor “run out” and “kick back”, care to elaborate on this a little for us laymen? :)[/QUOTE]
Hows life on the east coast? Still painting?
It is a fairly straight forward and normally an easily detected problem resulting from a rotor with irregularities; unequal thickness, bent or damaged or on some cars could possibly be caused by problems with wheel bearings.
An out of true spinning rotor on a car like a damaged or bent wheel on a bicycle with Cantilever brakes will rub/push against the brake pad every time it passes by the out of speck or uneven area.
On a car an out of true rotor will push the hydraulic brake calliper piston back into the calliper an exaggerated distance each time the irregular rotor passes by the brake pad to achieve clearance forcing hydraulic brake fluid back into the master cylinder.
The end result comes about when the brake system is re applied and an unusually large amount of brake pedal distance is required to move the fluid back into the calliper cylinder each time the system is re applied forcing the piston take up the slack between the rotor and brake pad.
Long, soft, inconsistant pedal!
Check the service manual, rotor run out can be measured with a dial indicator and measure all rotors only takes one to create problems.
Hey Marc, things are good here on the right coast. No more painting, got a gig as a site superintendent for a large construction company here in St John’s. Not doing physical labor for a living is definitely a plus.
Thanks for the reply. This brake problem is bordering on insanity. It seems that nothing I do makes any change. No matter how much I bleed lines or tighten nuts I cannot get the sponge to go away. I even just lowered the prop valve in case it was too high and trapping air, to no avail. Were your brakes working fine with the GSR brake booster and 1" master cylinder after you deleted ABS? Are you still selling that spare prop valve you had? Im going to start swapping out parts to see if I can get any change.
As for the rotors, they are rusty and most likely not true since the car has been sitting for a long time without being daily driven, however the car is on jack stands so I doubt a rotor out of true would affect much. Should I just have them turned and get new pads since it needs to be done anyway I wonder? Thanks for your help, I am truly desperate here. I have never had a problem on this car i couldn’t fix…Until now. :S
id just get rid of the abs anyway, thats just me
I already did. Same problem as OP with ABS
Brakes worked much better after removal of the ABS. I have sold the prop valve and GSR brake boster and only have the 1" master cylinder still for sale.
If the car is on jack stands rotor kick back is not your problem. Have you considered something like I initially recommended to OttawaGSR plugged into you system in various locations to diagnose your problem at less cost and time then throwing parts at it. Or even just capping off portions of your brake system systematical until you discover your problem through process of elimination.
http://www.jegs.com/i/Stainless-Steel-Brakes/884/A1704/10002/-1?parentProductId=755048
Or something like these:
http://www.brakequip.com/fitting11.html
These sound like nice to have items however form you description does not sound like the cause of your soft pedal.
Good to hear your making money and enjoying life, what are you building?
Thanks for the info Marc, much appreciated. So glad to hear about the car working better without ABS as well. My last integra stopped on a dime and it’s something I am anxiously looking forward to again.
I changed out the MC with an old one I had, only to discover that the newly installed one was bypassing and didn’t work at all. I now have zero leaks on all my fittings and everything is routed properly so I am leaning very heavily toward the MC. Next though i am going to service each caliper to ensure nothing is dragging or seizing in case that might be an issue (Needs to be done anyway so I may as well whilst I have the system depressurized…Again)
As for your MC, I might be interested. Perhaps I will shoot you an email to discuss. I really am leaning toward this being the problem as it is the only rational solution at this point. Everything else seems fine and the MC will cost less than the pressure testing kit.
On the bright side, I am learning a whole lot about how this brake system works!
P.S. As for the job we build about 70 homes a year at the company i work for. it’s a fast paced pressure cooker at times but I’m loving it.
I’ll shoot you an email re: the MC. Thanks again!
this sux bro…
Just throwing this out there, but have you tried the pushrod adjuestment on the inside of the firewall? I didnt see that mentioned as being checked? Perhaps it is way out of adjustment?
[QUOTE=cdscivic;2220711]this sux bro…
Just throwing this out there, but have you tried the pushrod adjuestment on the inside of the firewall? I didnt see that mentioned as being checked? Perhaps it is way out of adjustment?[/QUOTE]
Good call cdscivic. I have checked the play and it isn’t horribly out however, if everything else fails (and even if it doesn’t) Im probably going to give this a shot. Here’s the link in case anyone is interested. AWESOME FAQ by the way if any of yo or the OP has not seen it.
http://www.tegger.com/hondafaq/mastercylinderreplace/adjustment.html
np dude, I have had issues that drove me nuts before so I totally understand lol. Good luck!
Also, the Tegger site is alot of great info.
I fixed it. Two years, it took!
cdscivic from G2IC was right on the money with the adjustment of the booster’s pushrod. I had already figured it out by the time I read his post.
A few days after my last post, I picked up a booster from a local wrecker for $75. I had changed every other physical component between my foot and the wheel, save for the booster, so I justified it as peace of mind - just so I could say I did it.
While the original booster ended up not being faulty, I never would have figured it out had I not changed it. This is how it all went:
Reading the instructions in the Acura manual along with other sources, I saw how there was a lot of difficulty adjusting the pushrod clearances once the booster was installed. I thought to save myself some time by holding the two boosters side by side and making the replacement’s pushrod the same length as that of the original. They were way off, but I figured it was just the wrecker messing with the adjustment to ease removal from the donor vehicle.
I adjusted the replacement part to match the original and installed it into the car. After bleeding the brakes, the pedal was still soft. I did expect it, but was still a little depressed. Talking with friends about how it went, they asked if I followed the instructions exactly. I said I had, except where I adjusted the pushrod outside of the vehicle rather than after it was bolted to the firewall. I was encouraged to do it exactly as per the instructions.
So under the foot-well I crawled, only to discover it was, in fact, very much out of adjustment. And everything came together.
The pedal had to be lowered more than 2/3’s of the way down before the booster’s pushrod would even contact the master cylinder’s. After bench bleeding a master cylinder in a vice, I typically install the unit to the booster and run the lines back into the reservoir and “firewall-bench bleed” it again. I do this just in case air works into where the lines connect during the time between unplugging the hoses and attaching the hardlines. Because of the space, I never worked out the last bit of air. Without the extra push from the booster, my foot was not able to compress the air which is why I experienced a firm pedal with the engine off. Once running, the booster would assist and compress the air that was trapped in the system.
This also made bleeding a longer process, which was something I noticed before but dismissed.
Now my brakes are unbelieveably firm - so firm, I have to loosen them a little because they drag after they warm up!
I can’t believe that after all this pain and heartache, it was just a tiny adjustment. I feel a little silly, but hopefully some of you out there will benefit from my story and save yourselves two years of agony!
That is great news man, just wish I saw this post sooner lol … nonetheless, glad you got it all fixed up. Now if this is Zens issue, you guys will be totally set!
Glad you where able to figure your issue out. I just went and adjusted mine and have a shop do a Motul 600 fuild change and bleed. Hopefully this fixes my issue too.
I wish I had those tools so I can adjust my pedal
MattyG2, just make the tools like the guy in the link I posted above. That’s what I’m gonna do.
Ottawa GSR Awesome news man! Must have been an amazing feeling to finally figure this out. 
And on the bright side, there is nothing about your braking system that you don’t know about, or can’t fix. Great job and thanks for updating the thread!
I’m lazy and just want the tools
FYI if you do this go get the proper Honda Pushrod Adjustment Tool - part number 07JAG - SD40100, if not your brakes could rub and lock up on you (from experience).
good to hear that you got the problem resolved. i guess i’ll have to try and adjust the push rod or replace my booster too huh! not that you haven’t been helpful to anyone of us or anyone in the future by solving this problem but it would’ve been awesome to see a picture of your old and new booster. haha i guess if anyone of us tries to fix a similar problem that person can put up pics.
Update: Three months of spongy brake hell are over!
Same problem as OttawaGSR, that effing booster push-rod. I had seen the DIY before but didn’t try it cuz I figured it was a giant pain in the ass and probably wouldn’t work. After ready about the OP’s success and my problems being so similar, I figured I’d give it a shot and it worked!
Huge props to you OP, and thanks as well to cdscivic and everyone else who chimed in to help. I can’t believe it’s finally over and I can drive my teg again.
In case anyone missed it, here is the link that saved my ass. http://www.tegger.com/hondafaq/mastercylinderreplace/adjustment.html
G2IC Saves the day once again. Thanks guys!!!