Brake bleed problems
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Joined: Feb 2003
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From: Ankeny IA
Brake bleed problems
While swapping wheels I decided to clean and paint the brake calipers and flush the fluid. I have speed bleeders and bled the brakes normally starting with the RR, LR RF, LF. Pedal went to the floor, service traction, handling warning. Bled them twice more to no avail. Cracked the lines at the master and had some work the pedal to make sure there was no air at the master lines, bled the system. Same result. Tried this twice more, same result. Tried manually bleeding a couple times as if I didn't have speed bleeders with someone in the car. Still no luck. The pedal will travel to the floor when you first hit the pedal. Pumping the brakes will firm up the pedal and it will feel normal, but if you let it set about 10 seconds it will go back to the floor. I worked on bleeding this thing for about 2.5 hours.
I'm thinking there are 2 possibilities. The first is that the master has somehow gone south (was working fine before I started on all this). The second is that air got into the ABS system. I'm leaning more toward the second option, but am wondering if anyone has experienced something similar. The only other thing I can think of to try would be to do more bleeding.
I'm thinking there are 2 possibilities. The first is that the master has somehow gone south (was working fine before I started on all this). The second is that air got into the ABS system. I'm leaning more toward the second option, but am wondering if anyone has experienced something similar. The only other thing I can think of to try would be to do more bleeding.
Le Mans Master
Joined: May 2006
Posts: 5,987
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From: DuBois PA
St. Jude Donor '11-'12-'13-'14-'15
Well if you cracked the lines at the Master, air in the ABS module is a very real possibility. Problem is only a Tech II can bleed the ABS module..
I don't think that explains why you couldn't get a pedal right after getting everything back together though. Unless a speed bleeder went bad, I don't have any experience with them though, sorry.
EDIT: You didn't remove and forget to put back on any of the sensor wires at the hub did you? I sak becuase you get AH and TC warnings.
I don't think that explains why you couldn't get a pedal right after getting everything back together though. Unless a speed bleeder went bad, I don't have any experience with them though, sorry.
EDIT: You didn't remove and forget to put back on any of the sensor wires at the hub did you? I sak becuase you get AH and TC warnings.
Last edited by tstar; Aug 9, 2010 at 12:32 PM.
Thread Starter
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Joined: Feb 2003
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From: Ankeny IA
I didn't remove any of the sensors. The warning only comes on when you extend the pedal past where it would normally bottom out (not all the way to the floor). As for the lines at the master, that was a suggestion on Z06 Vette I ran across. I barely cracked the line, had someone step on the pedal, tightened and the released. The other 2 times I have done this I hadn't touched the lines at the master, but I was running out of things to try.
Burning Brakes
Joined: Jul 2007
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From: hill billy hell
Not true. The Snap On Solaris can perform the same automated bleed function as the Tech II.
My friend did all most the same as you. He removed his calipers to paint them left the lines open over night, and had problems bleeding them the conventional way.
He had to use my friends Solaris to completely bleed the system.
Find someone with a Tech II or Snap On Solaris and you will be good to go, unless you just have crap luck and need a master cylinder.
My friend did all most the same as you. He removed his calipers to paint them left the lines open over night, and had problems bleeding them the conventional way.
He had to use my friends Solaris to completely bleed the system.
Find someone with a Tech II or Snap On Solaris and you will be good to go, unless you just have crap luck and need a master cylinder.
Resident moron
Joined: Jun 2003
Posts: 4,746
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From: Assachusetts
Just curious, did you have the ignition on when you were bleeding? I ask because you said you were getting warnings while you were bleeding. I believe the ignition should be off. Though I'm not sure if it makes any difference, I know I have never bled the brakes on any vehicle with the ignition on.
As far as your problem goes, you say that you pump the brakes with the car off, the pedal firms up. But if you hold pressure, it slowly drops to the floor? That isn't good. It should stay firm. Are you sure you're not leaking brake fluid anywhere? If you have air in the ABS system, the brakes are just going to be a little spongy. It wouldn't cause the problem you mention. If the pedal is dropping with the ignition off, then I'm guessing you either have a leak, a faulty MC, or maybe even a faulty booster (vacuum leak maybe?)
Dope
As far as your problem goes, you say that you pump the brakes with the car off, the pedal firms up. But if you hold pressure, it slowly drops to the floor? That isn't good. It should stay firm. Are you sure you're not leaking brake fluid anywhere? If you have air in the ABS system, the brakes are just going to be a little spongy. It wouldn't cause the problem you mention. If the pedal is dropping with the ignition off, then I'm guessing you either have a leak, a faulty MC, or maybe even a faulty booster (vacuum leak maybe?)
Dope
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From: Ankeny IA
Just curious, did you have the ignition on when you were bleeding? I ask because you said you were getting warnings while you were bleeding. I believe the ignition should be off. Though I'm not sure if it makes any difference, I know I have never bled the brakes on any vehicle with the ignition on.
As far as your problem goes, you say that you pump the brakes with the car off, the pedal firms up. But if you hold pressure, it slowly drops to the floor? That isn't good. It should stay firm. Are you sure you're not leaking brake fluid anywhere? If you have air in the ABS system, the brakes are just going to be a little spongy. It wouldn't cause the problem you mention. If the pedal is dropping with the ignition off, then I'm guessing you either have a leak, a faulty MC, or maybe even a faulty booster (vacuum leak maybe?)
Dope
As far as your problem goes, you say that you pump the brakes with the car off, the pedal firms up. But if you hold pressure, it slowly drops to the floor? That isn't good. It should stay firm. Are you sure you're not leaking brake fluid anywhere? If you have air in the ABS system, the brakes are just going to be a little spongy. It wouldn't cause the problem you mention. If the pedal is dropping with the ignition off, then I'm guessing you either have a leak, a faulty MC, or maybe even a faulty booster (vacuum leak maybe?)
Dope
The initial pedal push is spongy and will go to the floor. Subsequent pedal pushes will firm up the pedal. Let it set for 10 seconds and it's back to spongy. Though it is possible the MC or the other things you mention may be bad, it doesn't seem likely they would go bad like this.
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From: Ankeny IA
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Resident moron
Joined: Jun 2003
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From: Assachusetts
The initial pedal push is spongy and will go to the floor. Subsequent pedal pushes will firm up the pedal. Let it set for 10 seconds and it's back to spongy. Though it is possible the MC or the other things you mention may be bad, it doesn't seem likely they would go bad like this.
You didn't let the master cylinder run dry at any point right? That can introduce air into the MC, requiring a bench bleed after that.
Dope
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From: Ankeny IA
No leaks I could see (and I spent a lot of time around the car). The brake pedal exhibits this behavior with the car running. The MC should not have gotten air into it, but it is a possibility. If so what is the procedure for a bench bleed of the master cylinder? The only info I found was what I tried earlier, just cracking the lines open very slightly while someone worked the pedal.
Advanced
Joined: Jun 2010
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From: Miami FL
Just a FYI I am going to a brake problem situation with the bleeding on my Vette. From what I read I believe you have a ABS VI(6) and you can manually bleed the ABS. According to the following website the ABS 7 was introduce in 1999 but replaced the ABS VI(6) in 2000, it provides instructions on how to bleed ABS VI(6).
http://www.aa1car.com/library/abs_bleeding.htm
http://www.aa1car.com/library/abs_bleeding.htm
Resident moron
Joined: Jun 2003
Posts: 4,746
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From: Assachusetts
No leaks I could see (and I spent a lot of time around the car). The brake pedal exhibits this behavior with the car running. The MC should not have gotten air into it, but it is a possibility. If so what is the procedure for a bench bleed of the master cylinder? The only info I found was what I tried earlier, just cracking the lines open very slightly while someone worked the pedal.
Have you tried seeing if the pedal firms up and STAYS firm with the car off? Just curious. If it does stay firm then everything is probably working fine, the really soft pedal is probably in fact a lot of air in the system as you are guessing. I honestly don't remember the bench bleeding procedure, I did it maybe 6 years ago or so. You can find it with a search. It's pretty simple.
Personally I'd try something like a Motive pressure bleeder. Even if it doesn't solve your problem, it is wonderful and easy to use for bleeding/flushing the brakes on any car. Good investment regardless. If doing a flush with the pressure bleeder doesn't help your situation, find someone with a Tech II or similar device that can bleed the ABS unit and see if that helps.
Those are your next steps, in my opinion.
Dope
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