ABS Problem? Please help
Thread Starter
Burning Brakes
Joined: Mar 2005
Posts: 1,112
Likes: 1
From: Torrance CA
ABS Problem? Please help
On a few occasions this past week, my front end started vibrating a lot after getting up to speed on the highway. I thought it was the tires since they were very worn. I had them replaced yesterday. Well, the vibrating happened again tonight, and now I know it is the brakes. I pulled off at the next exit and the rotors were very hot to the touch. Not surprising that it didn't take any pedal travel to engage the brakes.
Is this the ABS system warming up? The problem always seems to go away after a few minutes, but I am concerned there is more to the problem than just worn pads/rotors. My car has 34k on it so the warranty will be over next week as I am driving my car back home to SoCal. What should I do?
Is this the ABS system warming up? The problem always seems to go away after a few minutes, but I am concerned there is more to the problem than just worn pads/rotors. My car has 34k on it so the warranty will be over next week as I am driving my car back home to SoCal. What should I do?
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
i'm assuming the problem is happening without stepping on the brake.
are you sure the wheels are balanced,though that would have nothing to do with the brake pedal being hard.the rotors would be hot from braking normally.
does it feel like it takes more throttle to move the car than usual?
if you say the problem goes away after it warms up,are you talking about the vibrating or both the pedal is normal and the vibrating are gone?
are you sure the wheels are balanced,though that would have nothing to do with the brake pedal being hard.the rotors would be hot from braking normally.
does it feel like it takes more throttle to move the car than usual?
if you say the problem goes away after it warms up,are you talking about the vibrating or both the pedal is normal and the vibrating are gone?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Well,,,,I can feel for you! I have actually been in your shoes! 
The wife and I were having issues with the EBTCM on my 02 Z06. It was throwing a couple of codes. The real pisser was it was only 30 days out of the OEM 3/36 warranty!
One day, the wife took the Z out for a drive and came back about 30 min's later and stated that the brakes were applying all by them selves!
I thought "NO WAY!" and took the car for a drive and couldnt feel any issues. The next day I took the car for a drive and sure as hell, the ABS was applying "ALL BY IT SELF"
The ABS uses a pump to build pressure and poppet valves to apply and release the pressure to what ever wheel the system detects that needs ABS assistance. It will apply and release the pressure in very rapid pulsations.
So,,,,,,,,,,it is very possible that you are detecting sporatic ABS operation.
Do you have any ABS or EBTCM DTC error codes stored in the DIC memory? You need to check and post the results.
Here is how you check:
This is the absolute best C5 Code web site!!!
http://www.corvettedoctor.com/Code_Main.html
Please let us know what you find. We have some really good info on troubleshooting this system.
Bill C
The wife and I were having issues with the EBTCM on my 02 Z06. It was throwing a couple of codes. The real pisser was it was only 30 days out of the OEM 3/36 warranty!
One day, the wife took the Z out for a drive and came back about 30 min's later and stated that the brakes were applying all by them selves!
I thought "NO WAY!" and took the car for a drive and couldnt feel any issues. The next day I took the car for a drive and sure as hell, the ABS was applying "ALL BY IT SELF" The ABS uses a pump to build pressure and poppet valves to apply and release the pressure to what ever wheel the system detects that needs ABS assistance. It will apply and release the pressure in very rapid pulsations.
So,,,,,,,,,,it is very possible that you are detecting sporatic ABS operation.
Do you have any ABS or EBTCM DTC error codes stored in the DIC memory? You need to check and post the results.
Here is how you check:
This is the absolute best C5 Code web site!!!
http://www.corvettedoctor.com/Code_Main.html
Please let us know what you find. We have some really good info on troubleshooting this system.
Bill C
Last edited by Bill Curlee; Dec 28, 2005 at 10:02 AM.
Burning Brakes
Joined: Oct 2005
Posts: 924
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From: Atwater CA
2024 C7 of the Year Finalist - Unmodified
Team Owner
Joined: Dec 2003
Posts: 21,840
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From: When all is said and done... there is a hell of a lot more said than done. Riverside,Texas
St. Jude Donor '05 thru '26
Team Owner
Joined: Dec 2003
Posts: 21,840
Likes: 140
From: When all is said and done... there is a hell of a lot more said than done. Riverside,Texas
St. Jude Donor '05 thru '26
Thread Starter
Burning Brakes
Joined: Mar 2005
Posts: 1,112
Likes: 1
From: Torrance CA
Following all the good advice, I just went out and checked. There are only a few codes checked into the history and they are all unrelated to the brakes. That probably rules out the ABS system which is good to know.
You are correct that it takes more throttle to move the car (DIC says gas mileage goes down too). The problem does disappear completely when the car warms up after a few minutes on the highway. Strange.
A related thread I posted came back with suggestions that the pads are nearing the end of life and that the brackets may be bent.
Thanks for all the help.
You are correct that it takes more throttle to move the car (DIC says gas mileage goes down too). The problem does disappear completely when the car warms up after a few minutes on the highway. Strange.
A related thread I posted came back with suggestions that the pads are nearing the end of life and that the brackets may be bent.
Thanks for all the help.
Drifting
Joined: Oct 2003
Posts: 1,540
Likes: 0
From: bloomfield nj
sounds like either something is sticking.almost like you have a bad master cylinder or something to that effect.from what you are describing it sounds like pressure is being bled off until the car warms up[brakes stayed applied].for ha-ha's look at the rotors,see if 1 or more rotors look blue[from heat],if so,i would guess that is the brake hanging up.i tend to think your problem is brake related not abs related[the abs pump when activated will make the pedal move up/down not make it solid]and you will hear the pump run.
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