Hello all! I have a '97 camaro v6 base model and i have 2 problems i would like some help with.

1. I have a mix of issues with brakes. First of all, brakes operate normally the first 5 min of driving, then everytime when i was coming to a stop a LOW TRAC light came on just before i stop and i lost pressure in pedal for few seconds until it came back and stopped with a little noise from the rear brakes (drums). I had my mechanic taking a look at it and he told me something about losing oil from differential something and my rear brakes were DONE and destroyed (it was true, i saw them), so he cleaned, replaced, refilled what he had to and installed new brakes and stuff (don't know a lot about brakes, probably i should =-/)... but now problems persist, same thing, drives normally for few min, LOW TRAC light and the lost of pressure in pedal before a full stop; it works like that until ABS INOP light comes up and then brakes work "fine", i don't lose pressure or anything, but ABS INOP is on constantly. My emergency brakes also don't work 100%, it makes a loud noise and it moves a little bit. My bet is that it might be a wheel speed sensor, but im wondering how can i diagnose that and evaluate other posibilities. thanks for any input.

2. I have a hissing noise when i push gas pedal. I had a leak in egr tube, i replaced tube and valve and fixed it but i hear a quieter hissing noise when i rev up, it sounds like somewhere under the egr. It does not misfire but i think i lose power. I would appreciate any input on the subject. Mechanic told me something about an Idle pulley or valve, not sure, i started losing trust in that guy after he could not fix the brakes. Its so hard to find a reliable mechanic that wont strip you from your last penny =-/.

Lastly i always post in the wrong place, i'm sorry about that and i'm not sure if its the case now. Luckily i always get redirected. Thank you for that and any help on my issues. Have a great one.

 

Update: the hissing sound can be heard only when in gear, I mean when I push the gas pedal in D position, it does not happen in P nor N. that's basically why is so hard for me to figure out where the sound comes from :-/. Thank you.

 

Check break booster and break vac line.

 

Have you checked the level of your brake fluid?

 

I checked Booster... seems to be ok, no noises, no leaks, when i drive, the hissing sound comes from below... like exhaust maybe, im not sure. Someone told me some cars have a vac line from transmission and that could be from under, is that accurate?

I drove into a huge hole on the road with the front passenger side wheel and my brake problem issue with the LOW TRAC and ABS INOP got fixed (Temporary I assume) so ill check wheel speed sensor/wire in that tire.

Thanks for input.

 

That's accurate, but does not apply to your trans as it's electronically controlled.

A good way to find the hissing is to get the car up on jack stands (all tires or rear tires off the ground) and with a helper have them put the car in gear with their foot on the brake (E-brake on too for safety) and craw under and listen for the hissing.

As far as the ABS light issue goes. Mine comes on from time to time as well. The only reason I do not bat an eye at is because ABS only functions during panic braking and being someone who grew up around vehicles without ABS and in some case, no power brakes with drums all around, I know how to panic brake without ABS.
In your case, when the light is on, stop at local Advance/O'Riellys/Autozone and have them scan the car. Most of auto parts store use a code reader that can read ABS codes as well. This will point you in the right direction on where to look for the problem.