L8NiteAutomatic

Hello, I have finally got my '94 LT1 Z28 to run properly. replaced knock sensor, coolant sensors, temp sensors, and fuses. My last problem is that my ABS Inop and Brake lights are both on. I have not had problems with the brakes at all until recently. My rear driver's side rotor is grinding and it seems the rotor and pads need to be replaced. I replaced both my front rotors and pads 6 months ago and they still look great. The strangest part is my rear passenger side rotor and pads look almost newer then my ffront rotors and pads.

My questions are could it be that my brake line is broken on my rear passenger side and would that turn my ABS and brake light on?
-AND-
Since i just drove 200 miles today in mostly bumper to bumper traffic and my rims are now bright orange, would that make my caliper shot too? My initial conclusion was to just change the rotor and pads and call it a day.
Thanks

charliediss

L8,

Although I am not an expert on brakes, I can tell you a few hit points that will get you going in the right direction.

1) Believe it or not if your 3rd (high mount brake light) is out, it will disable your ABS, it is located in your spoiler.
2) There is a wheel speed sensor located in each wheel hub, if it has gone bad than that will also disable your ABS, if this is the case you will need a new wheel hub.
3) On the top of your differential there is a vehicle speed sensor, it is held to your differential by one bolt and plugs down about 3/4 down into your rear end, if it has gone I would recommend you go OEM, either Delphi or AC Delco, I have had good luck with the.
4) Finally, your ABS unit could be bad (let's hope it is not that).

Some good notes:

A) Your wheel hubs are interchangeable with LS1 style if you decide to go salvage yard.
B) Before you buy anything, make sure you check all electrical connections for rub-through or damage, your car is a 94 and has some serious wear under its belt.
C) Changing pads and rotors will not help your ABS situation.
D) If your rims are orange, it is because you have excess heat built up in the brakes, check each caliper for proper operation by jacking it up and doing a physical inspection. You will need the vehicle running and someone in the drivers seat to apply the brakes when you spin the tire. Exercise extreme caution while doing this.

Good luck, hope you figure it out.

Charlie

Injuneer

The "BRAKE" light comes on to tell you there is uneven hydraulic pressure in the front and rear lines. Could be air in the system, a leaking line, a kinked line, low fluid level in the reservoir allowing air into the system, or internal leaking in the master cylinder between the pistons for the front and rear brakes.

Logically, if you have a "BRAKE" problem, the ABS system is not going to work.

The "orange" is most likely rust, from the fine iron particles being created when your steel pad backing plates gouge into the rotors and shred them. Definitely gone far beyond the point where maintenance was required.

charliediss

Strangely enough, I jack up my car today to swap the vapor canister and purge valve and noticed that my driver side rear caliper is shot! It is still functional, but it is leaking fluid pretty bad. Just thought I would let ya know, these brake systems are not hard to work on. Good luck.

Charlie

L8NiteAutomatic

i replaced my rear brake pads and rotors yesterday. And yes, the pads were gone and the metal backing was straping into the rotor, both were replaced. Now the orange is gone and so is the noise. But the ABS and Brake lights are still on. when swicthing out the rear rotors and pads i noticed the passenger rear pads werent as eroded as the driver side pads. I also looked up brake bleeeding procedures and noticed the furthest brake from the master cylinder (pass rear) should be bled first. Could the hydraulic pressure be off on my passenger rear only between the rest and make it so the pads dont work as much and thats why they didnt really need to be replaced yet (they were replaced at the same time the previous replacement i believe) AND trigger my Brake light on and my ABS to malfunction?

One last question, in the Haynes camaro repair guide it states that cars with traction control could not be bled without a tach-1. My traction control is on, but the fuse is missing (car came without the fuse and i just replaced the bulb in the instrumental cluster and that turned the asr off light on) so im not sure if the car has traction control or not and if id still be able to bleed the system with it off.

Thanks for the help guys

L8NiteAutomatic

correction to "my traction control is on.." i meant "my traction control off light (asr off) is on.."

rngilliland

You don't have traction control. Traction control wasn't available on 94 models, they are ABS only.

Injuneer

Traction control was not available until 1995 models. It was advertised in the 94 brochures, but was never actually sold, as far as I know. It's even described in the 94 Owner's Manual.

Do you have a switch near your cigarette lighter labeled "ASR"? Do you have RPO code "NW9" on your build tag? Do you have a wired wheel speed sensor on the backing plate on the end of each rear axle? You would have all of those if you had traction control ("Acceleration Slip Control" on the Camaro).

On your dash, you have a "LOW TRAC" light that lights when the ABS activates. The dash also has an "ASR" light just below the top speed on the speedometer, if you have ASR. You have an "ABS INOP" light. You have the "BRAKE" light.

Which dash light are on?

If you have air in one of the rear bake lines, you will get the "BRAKE" light for differential pressure between the front and rear systems? The light does not come on for things like worn pads, rotors, etc. The most frequent cause of uneven brake pad wear is a caliper or a piston that is not free to move, and does not relax the pressure on the pads when you take your foot off the pedal.

L8NiteAutomatic

Ok, I have none of the things that come with traction control, all i have is the asr off light on because "I" placed a 161 bulb into its socket under the speedometer. I now believe the instrumental cluster could have been out of a 1995 model or newer. I will bleed the system and post after i have completed the bleeding process.

thanks

crankshaft23

my 94 has traction control i dont know how popular it is but i know there are 94 z28 with traction control

Injuneer

And your car has all the prerequisites for traction control:

-ASR Off switch next to the cubby above the console?
-RPO code "NW9" on the service parts tag?
-a large black and silver servo controller for the throttle cable, sitting on the top of the driver's side valve cover????

If so.... keep it. It's the only one in existence.