This is freaking me out. I have a 94 si hatch. When and only when my A/C is on my break pedal will have more travel before engagement and it will sink slowly while I slow down. It always stops the car but it is mushy. It feels like a master cylinder on the go but it doesn't because it will not sink while the car is at rest. It only sinks while the engine is revving down. This leads me to think of vacum as an issue. I am not losing break fluid.

My friend has a 93 coupe and he has experienced the exact same thing. Does anybody know about this? Oh, I've also got ABS so bleeding the system is out of my mechanical ability since I don't have the tools.

Thanks, Matt

 

oh, and this usually happens when it is hot outside. Could it be that the break fluid is getting too hot?

come on, I know this is not a super rare thing.

If this happens to you let me know. Thanks.

 

Im not an expert or anything so dont quote me on this, but Id guess that the problem is vaccuum related. The brake boosters on hondas are vacuum drivin so you might want to check if you have a vacuum leak if not a bad booster or what not.