Welcome to Camaro Z28!

Welcome to CamaroZ28.Com, the ultimate Source for Camaro enthusiasts! Here you can join over 90,000 Camaro enthusiasts from around the world discussing all things related to Camaros and more. You are currently viewing as a guest which gives you limited access to view discussions

To gain full access to our forums you must register for a free account. As a registered member you will be able to:
  • Participate in over 40 different forums and search/browse from over 5 million posts.
  • Upload your Camaro details to your Garage
  • Post photos, respond to polls and access other special features
  • Gain access to our free marketplace to buy, sell and trade Camaros, parts and more.
All this and much more is available to you absolutely free when you register for an account, so join our community today today!

If you have any problems with the registration process or your account login, please contact support.


Go Back   CamaroZ28.Com Message Board > 1967-2002 F-Body Technical Discussion > 1967-2002 Specific Technical Discussion > Suspension, Chassis, and Brakes
Sign in using an external account
Register Forgot Password?


Reply Post New Thread
 
 
LinkBack Thread Tools Search this Thread Display Modes
Old 04-20-2011, 06:58 AM   #1
Registered User
 
Join Date: Apr 2000
Location: Lynn Haven, FL
Posts: 119
1993 Issue - Low Trac, ABS INOP, & Brake Lights

I've had my '93 Z28 for almost 12 years and I've had this problem since the day I bought the car. I have some spare time on my hands and I'm ready to fix this issue. The problem below happens approximately 75% of the time I drive the car. Here we go......

Every time I start the car I disengage the ebrake (I have an M6) and I let the car warm up for about 30 seconds. I then put the car in reverse and begin to back up. While I'm in the process of moving backwards, I ALWAYS hear a faint grinding noise that lasts for just 1 second or so. The exact same time that I hear the noise I see on my dash that the "Low Trac" light flickers ON just for a fraction of a second. Once I finish backing out of my driveway, I put the car in 1st and slowly begin to move forward. After about 2 seconds of moving forward, the "Low Trac" light will flicker on again and then both the "ABS Inop" and "Brake" lights will come on and stay on for the duration of my drive. This happens about 75% of the time I drive my car (it's my daily driver).

I seem to remember about 10 years ago asking this question and I never really found out what it was. I think someone mentioned to me that the '93 M6s perform some sort of "Low Trac" check on startup but I can't really remember. I've tried searching but can't find anything that matches my exact situation. The car has always braked flawlessly and I've never had any issues other than the annoying lights on the dash and I've also always wondered why it makes that *grinding* noise as I begin to back up. I do all my own routine brake work (changing rotors/pads/fluid etc) but I have no idea where the "sensors" are or how to check them. Any help is greatly appreciated.
This ad is not displayed to registered members.
Register your free account today and become a member on CamaroZ28.com!
__________________
1993 Z28 M6

Last edited by CobraEatr; 04-20-2011 at 07:19 AM.
CobraEatr is offline   Reply With Quote
Old 04-20-2011, 07:11 AM   #2
Registered User
 
shoebox's Avatar
 
Join Date: Dec 1969
Location: Little Rock, AR
Posts: 26,916
Re: Question for Shoebox & Co: 1993 Issue - Low Trac, ABS INOP, & Brake Lights

Sensors are in the rear of each front wheel hub and in the top center of the rear end housing. I would check what you can of the wiring and connections. A scan for ABS codes might help (you will need a scanner capable of reading them). The ABS system is highly complicated and takes up hundreds of pages in the service manual. I've really had no particular dealings with it.

If you want a particular person's attention to a thread, send them an email with a link. Putting a name in the title only makes other people avoid the thread and lessens your opportunities for getting more help (MHO, of course).
shoebox is offline   Reply With Quote
Old 04-20-2011, 04:51 PM   #3
Super Moderator
 
Injuneer's Avatar
 
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 41,293
Garage
Re: Question for Shoebox & Co: 1993 Issue - Low Trac, ABS INOP, & Brake Lights

Couple points:

Please don't "page" individuals on the tech forums. If you want feeback from a specific person, send a PM or an e-mail.

Please post on the correct forum. None of the above relate to the "engine". These topics get discussed regularly on "Suspension, Chassis and Brakes".

Thanks.

Moving.
__________________
Fred

94 Formula A3+1: 381ci all-forged stroker - Callies Stealth, Oliver 5.85 billet rods, BME nitrous pistons / CNC LT4 heads / Comp Cams custom solid roller / TH400 + GearVendors OD / Strange 12-bolt - 4.11's / 300-shot N2O / Spohn suspension / 6-pt roll bar with integrated SFC's / AutoMeter instrumentation / MoTeC M48Pro engine management system / a few other odds 'n ends. 800HP/800LB-FT at the flywheel.
Injuneer is offline   Reply With Quote
Old 04-22-2011, 12:28 AM   #4
Registered User
 
Join Date: Jul 2010
Location: Westminster, CA
Posts: 349
Garage
Re: 1993 Issue - Low Trac, ABS INOP, & Brake Lights

I am a little confused how the car can brake flawlessly with ABS Inop and Brake warning lights on? Does the abs actually work when these lights are both on or can you lock up the brakes, i.e, you do not have functioning abs? I suspect you do not have abs when the warning lights are on.

"Easiest" way to determine what is wrong without replacing everything is to get a GM scanner which has the brake software in it; the tech 1s and 1As can be found on ebay for about $200-$300. Get the error codes and go through the factory manual diagnostics which requires manually cycling the abs unit with the scanner.

I have a 95 which is a little different than a 93 but I recently had the ABS Inop and Brake lamps (though both on at all times) and while the brakes worked in the sense they stopped the car, they did lock up, so no abs; turned out to be a bad abs motor pack.
__________________
1995 Z28 Convertible M6
1999 K2500 Suburban
2010 Nissan Cube (the wifes, I wear a wig and sunglasses when I have to drive it.)
2012 Volkswagen Routan SE (Crikey, now I own a minivan...)
pgerst is offline   Reply With Quote
Old 04-24-2011, 07:18 AM   #5
Registered User
 
Join Date: Apr 2000
Location: Lynn Haven, FL
Posts: 119
Re: 1993 Issue - Low Trac, ABS INOP, & Brake Lights

I'm not sure if the ABS is working or not. One would assume that if the light is on then it isn't working, however I've never locked them up before and I've been making some pretty hard stops over the past 10 years. I'd rather not throw down a couple of hundred bucks for the scanner if I didn't have to.

Does anyone else with a M6 hear a slight grinding noise as they reverse and their "Low Trac" light flicker? I remember reading years ago that this was normal either for '93 M6 owners or all M6 owners. I can't remember exactly but I briefly had a conversation with another member back then about it.
__________________
1993 Z28 M6
CobraEatr is offline   Reply With Quote
Old 04-24-2011, 07:39 AM   #6
Super Moderator
 
Injuneer's Avatar
 
Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
Posts: 41,293
Garage
Re: 1993 Issue - Low Trac, ABS INOP, & Brake Lights

Have you ever pulled the sensor on top of the rear axle housing, to check for damage indicating contact with the reluctor, or heavy accumulation of metal particles?

My car was an M6 for the first 7 years of its life, and I never noticed a grinding sound in reverse, and never had a problem with the ABS.
__________________
Fred

94 Formula A3+1: 381ci all-forged stroker - Callies Stealth, Oliver 5.85 billet rods, BME nitrous pistons / CNC LT4 heads / Comp Cams custom solid roller / TH400 + GearVendors OD / Strange 12-bolt - 4.11's / 300-shot N2O / Spohn suspension / 6-pt roll bar with integrated SFC's / AutoMeter instrumentation / MoTeC M48Pro engine management system / a few other odds 'n ends. 800HP/800LB-FT at the flywheel.
Injuneer is offline   Reply With Quote
Old 04-16-2012, 05:42 AM   #7
Registered User
 
Join Date: Apr 2010
Posts: 9
Garage
Re: 1993 Issue - Low Trac, ABS INOP, & Brake Lights

had a similiar incident here, was the sensor Shoebox mentioned earlier
mediclafemme is offline   Reply With Quote
Old 04-16-2012, 05:42 AM
 
Reply Post New Thread

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
ABS INOP and TRAC OFF lights on our 2000 Bonneville JakeRobb F-body Lounge 12 11-07-2007 10:21 PM
TRAC OFF/ABS INOP Lights joecool72 Suspension, Chassis, and Brakes 0 01-23-2005 09:48 PM
ABS ipon, low trac,Brake lights on. MonoxideChild LT1 Based Engine Tech 9 03-03-2004 02:08 PM
ABS INOP and BRAKE lights on ChuckZ28 LT1 Based Engine Tech 5 11-06-2003 09:16 AM
ABS INOP, Low Trac, ASR, and Brake?!?!?!?! Black_Z28 LT1 Based Engine Tech 8 06-13-2003 10:32 PM


All times are GMT -5. The time now is 05:04 PM.


Copyright © 1996-2013 CamaroZ28.Com. All rights reserved.

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.