Sideways73

Ok so it is a 77, I replaced all the brake calipers, pads, drained and flushed out the entire brake system, and bled everything. The brakes worked awesome for a couple of months.

Now the car sat for month while I was out of town and when I press the brake pedal it makes an air whooshing sound the entire time the brake pedal is held down. The car still stops (checked in the driveway, not driving down the road like this because it is very odd) Nothing is leaking, the brake fluid level does not drop at all. I checked the vacuum at the brake booster it is around 15 PSI at idle, It almost sounds like when I hold the pedal down it makes a vacuum leak behind the firewall at the brake pedal. Any ideas?? Like I said the car still stops, though the brakes don't feel as good as they used to be and the fluid level doesn't drop. My first thought is the Brake booster is going bad?? Just wanted to see if anyone else had this happen before I start swapping parts out.

MelWff

I belive there is supposed to be a seal where the pedal rod goes through the firewall, is yours gone?

http://willcoxcorvette.com/product_i...oducts_id=8850

bobs77vet

it does sound like the diaphram has a leak, have you tried putting a vacuum pump on it to see if it holds vacuum?

Sideways73

I will try the vacuum pump tomorrow and see if that seal is there or has went the way of the dodo.... Thanks for the advice, hoping it isn't the whole booster, but if it is then that is just a reason to replace the master cylinder also since it will be off anyway!!!