YuckyCorpse

Okay so I have a crx hf with crx SI front brakes, 1990 integra rear brakes. I just got all new calipers, rotors and pads. I just replaced my master cylinder today.

Heres what the problem is, even before i replaced everything my pedal felt really easy to push in, and it would go down quite far. It would stop and hold, it wouldnt sink. I figured it just needed bled.

So I replaced the calipers, then bled them. The pedal feels nice and firm when the car is off. but then when you start it, the pedal goes in and feels soft. but it still stops and a certain point and doesnt sink.

So I got a bigger reman master cylinder for a 91 civic ex. "figured I should replace that as well. I bench bled the master cylinder until there were no air bubbles, kept doing it a for a few minutes after that to be sure it was bled. I installed it and spent a good while bleeding the brakes. I bled them in the correct order. a BUNCH of air came out. I bled them all until there was no air, i bled quite a bit of fluid after that to make sure it was all fresh. The pedal feels amazing when the car is off, it feels very firm, just perfect. But when i turn the car on the pedal gets soft, almost as if there is no resistance on it, and goes down a little before there is any resistance.

I took the car around the block and it felt the same as it did before i changed all the brakes, I took it to a parking lot and tried locking the brakes up, its very hard to stop, "feels the same as it did before" Then i noticed when i push in the brakes far enough, my idle drops to 300-450 rpms.

I thought i would inspect the check valve. I removed it and decided i would try to put it in backwards to see if maybe it was in the wrong way, of course the brake pedal was rock solid. I could barely press it, But heres the thing, my idle was perfect when pushing on the brakes. never dropped below 850

So maybe my diaphram has a hole in it? even my tuner couldnt figure out why my car idled weird sometimes.