Recently bought salvaged Rx 8 and the brakes aren't working ( E - Brake does however.). The brake pedal's just too hard to push down to the floor. I can press down about half an inch before it stops responding and is unmovable by my foot.

What I've done
I checked the hose stretching from the intake to the booster for vacuum leaks and while there is actually a leak , I don't think the hose is the source. I checked the BCV and it functions too so the problem lies with the booster?

Affects idle
When pumping brake pedal, my idle also increases by about a hundred RPMS with each pump.

I am pretty clueless when it comes to the brake system so I looked all this up last night and it sounds like a faulty part in the air flow between the two chambers in the booster. I'm just going to E bay one but before shelling out the dough, can anyone think of anything else that could cause the probrem? Don't want to spend the money and time fixing something that isn't broken.

Thanks.

 

Check the vaccum hose leading from the brake booster as well as the fitting itself.

 

Did you fix the issue? My car's idle goes up slightly when pumping the brake pedal too. Not as dramatic as yours though.

 

Doubt the OP is around anymore.
You bumped a 3 year old thread.

Maybe he'll reply, but I wouldn't hold my breath

 

If you think it's a problem, consider replacing the booster vacuum check valve.
They're pretty cheap.

 

Sorry guys. Thought it's better to comment here than start a new thread. My brake pedal gets stiff after 4-5 hours too. That indicates a leak right?