Brake problems
#1
Racer
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The local dealer has managed to screw up my brakes and doesn't have a clue what's wrong with them. Hopefully someone here may be able to sheld some light on the problem.
I have a 2005 C2S Cab. I am using Super Blue brake fluidand its been flushed 3 or 4 times in the past year. Twice by a competent shop and once or twice by the dealer (or not).
Started in Janury (yes, 7 months ago) when The dealer told me I needed pads and rotors to pass a tech inspection for a DE. I didn't have time to go elsewhere or do it myself so I had them do it.
On the track the brakes were pretty soft. They did not stop the car like the ones that had to be replaced did. I had about 400 miles on the brakes before the event so it not like they hadn't been bedded in.
I went back to the dealer and went out with their brake guy. He said they felt fine. I explained that they were nowhere near as strong as they had been. I went home annoyed.
Then I noticed that at slow speeds (<5mph) the PASM would kick in. It occurs randomly and it not repeatable. I took it back to the dealer and left it with them. They told me that another shop that had bleed the brakes for me seveal months earlier used a vaccuum bleeder and that would ruin the brakes. I called the othe shop and they said they used a pressure bleeder. I told the dealer that. I got the car back and the brakes were the same and the PASM still kicked in randomly at very slow speeds.
Then one day I was sitting in the car with the top down and someone walked by the passenger side of the car and back tracked. He made a comment about the wear pattern on my right side rotor. He said he had the same car and that the rotors shouldn't lok like that. I got out and looked and sure enough there was a wavy pattern and not smooth like every other rotor I've seen.
So I had to take the car back to the dealer becaue they broke the cover on the compartent of he drivers armrest when they fixed the spring on the door handle. I pointed out the wear pattern. They had the car a week. They couldn't explain the wear pattern. the car still did the same damn thing. But now I had a nice dent in the hood with gouges down to bare metal.
After 5 months of trying to get them to find me a slot to have the hood fixed I just took it in. We did have several nasty hail storms that made body shop times a rare commodity. I also said I wanted the brakes to work like they did before they told me I needed a brake job.
after a week and a half I got the car back Wed afternoon, took it home and parked it. Thursday morning I needed my brakes on the drive in and they weren't there. If I hadn't anticipated the idiot on the side of the road was going to do something stupid and let off the gas I would have hit him.
I took the car home that night and this morning I had roadside assistance trailer the car back to the dealer. I called the service manager this morning and told him the car was coming back. I told him the brakes were worse then when I left them. I also commented that the average gas milage went from 17.8 when I dropped it off to 10.2 when I picked it up. He couldn't explain how that happened.
I asked the SM just what they did when the car was in there last week and he said "nothing. We test drove it and verified tht the part numbers on the pads and rotors were correct." I felt I was remarkably restrained in not driving over there and ripping his head off.
So what would cause soft brakes and the nanny to kick in at very slow speeds? I can see the right side pressure fluxuating due to the wavy wear partens. that might cause the PASM to kick in. At higher speeds the fluxuations may get averaged out. But what is causing the wear patterns?
Paul
I have a 2005 C2S Cab. I am using Super Blue brake fluidand its been flushed 3 or 4 times in the past year. Twice by a competent shop and once or twice by the dealer (or not).
Started in Janury (yes, 7 months ago) when The dealer told me I needed pads and rotors to pass a tech inspection for a DE. I didn't have time to go elsewhere or do it myself so I had them do it.
On the track the brakes were pretty soft. They did not stop the car like the ones that had to be replaced did. I had about 400 miles on the brakes before the event so it not like they hadn't been bedded in.
I went back to the dealer and went out with their brake guy. He said they felt fine. I explained that they were nowhere near as strong as they had been. I went home annoyed.
Then I noticed that at slow speeds (<5mph) the PASM would kick in. It occurs randomly and it not repeatable. I took it back to the dealer and left it with them. They told me that another shop that had bleed the brakes for me seveal months earlier used a vaccuum bleeder and that would ruin the brakes. I called the othe shop and they said they used a pressure bleeder. I told the dealer that. I got the car back and the brakes were the same and the PASM still kicked in randomly at very slow speeds.
Then one day I was sitting in the car with the top down and someone walked by the passenger side of the car and back tracked. He made a comment about the wear pattern on my right side rotor. He said he had the same car and that the rotors shouldn't lok like that. I got out and looked and sure enough there was a wavy pattern and not smooth like every other rotor I've seen.
So I had to take the car back to the dealer becaue they broke the cover on the compartent of he drivers armrest when they fixed the spring on the door handle. I pointed out the wear pattern. They had the car a week. They couldn't explain the wear pattern. the car still did the same damn thing. But now I had a nice dent in the hood with gouges down to bare metal.
After 5 months of trying to get them to find me a slot to have the hood fixed I just took it in. We did have several nasty hail storms that made body shop times a rare commodity. I also said I wanted the brakes to work like they did before they told me I needed a brake job.
after a week and a half I got the car back Wed afternoon, took it home and parked it. Thursday morning I needed my brakes on the drive in and they weren't there. If I hadn't anticipated the idiot on the side of the road was going to do something stupid and let off the gas I would have hit him.
I took the car home that night and this morning I had roadside assistance trailer the car back to the dealer. I called the service manager this morning and told him the car was coming back. I told him the brakes were worse then when I left them. I also commented that the average gas milage went from 17.8 when I dropped it off to 10.2 when I picked it up. He couldn't explain how that happened.
I asked the SM just what they did when the car was in there last week and he said "nothing. We test drove it and verified tht the part numbers on the pads and rotors were correct." I felt I was remarkably restrained in not driving over there and ripping his head off.
So what would cause soft brakes and the nanny to kick in at very slow speeds? I can see the right side pressure fluxuating due to the wavy wear partens. that might cause the PASM to kick in. At higher speeds the fluxuations may get averaged out. But what is causing the wear patterns?
Paul
#2
Poseur
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It's unfortunate that someone in your service department doesn't know anything about brakes. This isn't like going to the moon. I believe that the entire system needs to be fully flushed,--the old fashioned way. Put a guy in the driver's seat and let him pump and they bleed at each point. If that doesn't clear it up they need to get more serious about determining the extent of the PASM kick in issue. Something is amiss. Is there another Porsche dealer around other than the one fill of idiots?
Your posting makes me feel so much better that I ordered the PCCBs. Expensive, but only need an occasional brake bleeding for the first 250,000 miles...
Your posting makes me feel so much better that I ordered the PCCBs. Expensive, but only need an occasional brake bleeding for the first 250,000 miles...
#3
Burning Brakes
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A soft pedal with new pads and rotors (assuming they are the correct parts at correct thicknesses) usually means air or water in the brake lines, or even a fluid lead (check the level in the brake reservoir often until sure). Some find flushing the ABS bits to be particularly vexing - a bit more complicated than pre-ABS cars from what I'm told.
Scoring on one rotor could be grit between the pad and rotor although you should have heard that. It seems like maybe just one corner is really braking for you (the corner with the scored rotor), the others are not getting the pressure to apply the pads properly. Thus the ABS kicks in (I doubt PSM is kicking in, and certainly not PASM which is the suspesion system) to try to grab the other wheels. If that's what's happening, maybe there is something blocking the lines or the master cylinder is failing. I say that because its hard for me to believe that there is air/water in three of the four brake lines after they've been flushed! That's the best guess I can offer, and I am certainly no expert on these systems.
Are there other symptoms (pulling to one side would be consistent with only one rotor getting the juice)?
But rather than diagnosing the brake system, it is easier and quite safe to say you have a defective dealer. Consider calling in PCNA.
Scoring on one rotor could be grit between the pad and rotor although you should have heard that. It seems like maybe just one corner is really braking for you (the corner with the scored rotor), the others are not getting the pressure to apply the pads properly. Thus the ABS kicks in (I doubt PSM is kicking in, and certainly not PASM which is the suspesion system) to try to grab the other wheels. If that's what's happening, maybe there is something blocking the lines or the master cylinder is failing. I say that because its hard for me to believe that there is air/water in three of the four brake lines after they've been flushed! That's the best guess I can offer, and I am certainly no expert on these systems.
Are there other symptoms (pulling to one side would be consistent with only one rotor getting the juice)?
But rather than diagnosing the brake system, it is easier and quite safe to say you have a defective dealer. Consider calling in PCNA.
#4
Racer
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I'd love to take it to another dealer. Unfortunately that's Houston or Dallas and that's a bit of a hike. But I'm getting close to that.
There is no scoring on the rotor and no sound. It's a wavy or rippling pattern on the rotor. I probably should have taken a picture before sending it back to the dealer.
There isn't any pulling when braking
There is no scoring on the rotor and no sound. It's a wavy or rippling pattern on the rotor. I probably should have taken a picture before sending it back to the dealer.
There isn't any pulling when braking
#5
The Penguin King
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It's not that uncommon for rotors to get grooved or look wavy as they get worn, so depending upon how grooved they are you may or may not have a problem there. A soft pedal is almost always a sign that you need to bleed the brakes. Make sure they also bleed the clutch, as the two systems share a common reservoir. As far as PSM kicking in (PASM is your active suspension, PSM is the stability system), you could have a bad wheel speed sensor. This would cause it to interact at the wrong times, and also possibly lead to brake problems if your brakes are constantly engaging as you drive.