Hi everyone,

I'm having some issues with the brakes on my 1995 Camaro. Calipers, pads, rotors, drums, etc. have all been done on the car. I've bled the air out of the system and replaced the brake fluid more than once, though I know with the ABS system on these that's tricky to be definitive about.

My car does brake, but the pedal is soft(er) feeling and travels fairly far. Not the feel I want, nor the feel I remember. The other new odd thing I have going on to go with this issue is a constant, somewhat higher pitched whine coming from the car at all times. RPM noticeably fluctuates when I press down/hold on the brakes, and the sound might(?) change a bit in pitch as well. From quick research, I wonder if I have a leak or some other issue around the booster/master cylinder. What do you think? I checked around there and don't have any fluid leak, nor has the fluid level in the reservoir changed.

 

Pressing the brake and having the RPMs drop is indicating a vacuum leak. The brake booster is prone to rusting and leaking. Also check for cracked vacuum hoses or inop check valves. The hoses crack alot in the most un-obvious locations. A good flashlight and mirror will help locate the issue. Good luck

 

Thanks for the response. So I guess physical inspection is the best for the valve and hoses, but any procedure on checking the booster itself for a leak?

 

vipe155,

You can usually find a leaking vacuum hose using a spray can of ether (aerosol spray "starting fluid"). Let the engine warm up, then idle. Spray around each hose, one by one. If the engine changes speed, you just sprayed ether into your vacuum leak.

You can check the "booster" (vacuum reservoir) by running up the engine, stopping the engine, and see how many times you can apply the brakes with assist. For the second part of the test, run up then stop the engine, wait a few minutes, and see if you have the same number of "assists" from the vacuum reservoir. If the "assisted" number of brake applications is very different from the first check, you may have a bad reservoir or a bad check valve in the system. The vacuum reservoir should hold enough vacuum to assist braking, several times. All of this testing is to be done in Park, with the handbrake set.

Keep us posted.

 

Thanks for all the help so far. I'll have some things to check over the holiday when I have the time.

 

I did the brake booster test, and both tests... immediately after turning off the engine and waiting a few minutes gave me two assisted pushes on the pedal before it firmed up solid. Also tested the check valve and it's working properly.

 

I don't know if this will help, but I have a couple of videos. First one has the extra whine sound I'm getting from the car now...but I'm wondering if it's really related to something else. Second video shows the rpm action when pressing the brake pedal down and releasing. I should note that the extra engine noise goes away in drive, but is present in park/neutral.

 

That whine might be your alternator or something else belt driven.
You could disconnect the belt and start the car,if the noise goes away you'll know it's something driven by it.

 

Yeah, I didn't even have to start the car. I had just figured the sound was related to the brakes, and since it varied depending on what you were doing with the car maybe it was a high pitched vacuum leak. But I loosened the serpentine belt and rotated the alternator pulley and it's all chirps and squeaks.

It's an original alternator, 172k. Is replacing the bearings (and anything else needed) myself something that can be done?

EDIT: After looking into it, I'm not sure either way. I'm all for keeping original parts and fixing things, but to me it's a difficult call. It's about $30-40 worth of parts/shipping to replace components (not just the bearings). After watching a video about how to tear down a CS130 alt. there is a decent amount of work involved, and I don't even have an impact to get the pulley off.... So it's that vs. paying $90 for a new ACDelco w/2 year warranty.

Still don't know what's up with the brake pedal feel. The RPM jumping is a vacuum leak symptom?

 

I'd just take it as a core to your local NAPA and get a replacement or buy that Delco,it's not like the alternator has vin numbers to match to the car.
You might also be able to find a local shop that rebuilds starters and alternators,I tok the starter out of a Harley I had to a local shop,they said all it needed was new brushes and had me fixed up for $30,Harley didn't even sell rebuild kits just new starters for $400!
RPM jumping could be a lot of things but certainly could be a vacuum issue and could affect your brake booster.