weirdest thing ever! I've been building race cars and turning wrenches for >10 years at this point so I'm not an idiot and I can not for the life of me figure this one out. Help is very much appreciated!

2000 Honda civic si: when you have the steering wheel straight or turned towards passenger side all is good and brakes are beautiful, turn to the left and the pedal goes to the floor with maybe 10% of braking power left at most. Turn it back straight and within 2-3 pumps brakes are back to perfect. Do this 10 times and car reacts identically each time and brakes come back to perfect. With wheel cranked to the left, with pedal on the floor and brake system failing, if you pump the pedal you can feel something trying to pull the steering wheel straight a little. once steering wheel is straight the pedal is firm with zero slop and requires no pumping, no indication of air in the system and brakes recover 100% each time.

brakes do this identically even when car is off and not running.

Can't for the life of me even figure out how this is POSSIBLE?

already replaced:
all rubber brake lines
master cylinder
new pads and rotors
booster looks great
calipers look great as well and no signs of any fluid leaking anywhere.


how is this even possible? any guesses on where to look next?! I'm at the end here and can't figure this out.....



thanks ht!

 

Your suspension forks are switched.

 

Put the car on jack stands and remove the front wheels. Have someone else turn the steering wheel and visually inspect if something is binding up the rubber lines and pinching them or causing them to stretch/pull the caliper back.

 

This is really interesting because we just put a new clutch in the car so this could be totally possible. Could you explain how having the forks on wrong side could cause this? Did this happen to you too?

Thanks!

 

Thanks man! I've done what you describe a few seperate times now and no binding or weirdness when the wheels are turned up on jack stands. Plenty of slack in the lines when turned full lock in either direction and I removed the calipers and took them apart and they look great.

So bummed about this as it is my sisters car she needs for work so driving me crazy!

Thanks guys

 

So this only happens when the car is on the floor, with wheels and the weight of the car on it?

Are you able to crawl under the car and inspect it when it happens?

 

Check the brake hose (either side, front) for binding or stretching when turning. That would be caused by the wrong rubber hose, or having the hoses routed incorrectly.

Also, recheck that the banjo bolts where the hoses go into the caliper are tight, and that the copper crush rings are in good shape.

 

Thanks joey, it happens the same whether car is up on jack stands with wheels off or if on the ground and driving around. The thing that trips me out is that the brakes come back literally 100% after you turn left and they fail too. Once they're back they feel amazing too, super firm with no slop.

so weird....

 

Strong username to thread title.

 

Yes, it did. The forks are curved. When they're flipped, they push the caliper off the disc, which compresses the piston. You have to pump the brakes to seat the pad back on the rotor. It's exactly what your problem is.

 

EPIC. that totally makes sense, especially since the front suspension was just apart for new shocks and clutch. Thanks! going to go check this now. fingers crossed this is it!

I heart honda-tech

 

hahah....I haven't given up yet!

 

just wanted to say "thanks" Mr. NotaRacist, as this turned out to be exactly what it was. this car is a bastard step child of random parts and it turns out the huge integra calipers for some reason were hitting the suspension forks and pushing the calipers away and causing this issue. I think before we rebuild the suspension the various worn bits were allowing enough play that this wasn't happening but once bushings and ball joints were all replaced this issue surfaced. I just took a dremel and ground a small amount on the suspension fork and caliper and it works perfect now.

the caliper was just barely hitting the EM1 suspension so it wasn't obvious but still not sure how I missed this but problem solved and hopefully if anyone else runs into this they can find this thread.

 

Good call NAR. Kudos on insightful diagnosis.