99 Camry Brake Power Booster going bad?

[ccyphers]

Hey folks. My wife’s 99 Camry recently started making a hissing noise near the brake pedal area. It started hissing when she pressed on the brakes but has since started hissing all the time…..when her foot is on and off the brake. I tried pumping the brake with the car turned off to build up pressure, kept my foot on the brake and started the car and the pedal went almost to the floor. I checked under the dash and the sound is coming from the pedal area. I also checked under the hood and the sound seems to be coming from the brake power booster area. Upon putting my ear closer to the booster in the engine compartment, the sound seemed to be more towards the engine and maybe not from the booster itself. Kinda hard to tell where the sound is coming from under the hood with the engine running.
1. Does this sound consistent with the power brake booster being bad?
2. If it is the brake booster, how difficult is it to replace for a simple do-it-yourselfer?
3. Anyone know of the typical cost to have one repaired at the dealership?

[Brian R.]

If you didn't, check your vacuum lines to make sure there are no cracks in them. Also check the various vacuum connections to make sure they are not broken and leaking. Many of them are plastic and can break with very little effort.

It is possible that you have a bad seal or diaphram in the booster, but rule out the vacuum lines and connections/nipples first since they are potentiall cheap to fix.

[Airjer_]

Or you could pinch off the rubber vacuum line going to the booster and see if the noise goes away.

Or remove the hove from the booster, block it off, and see if the noise goes away.

Of it does than you on the right track with the booster starting to leak.

[gator2764]

You can expect to pay 700-1100 for a new booster. I am not sure if you can do this with the camry but look and see if the fluid res. is bolted to the booster. If so take out the bolts and slide the reservior out and look inside the booster to see if any fluid is in there, it should be dry.

[ccyphers]

Thanks everybody for the responses. Turns out the master cylinder had a leak and was causing all the noise. Ended up costing $600 for new master cylinder, new rear brakes and bleeding the brake lines. Not too bad (I guess) but I’m sure I could have found another way to spend $600.