Brake failure need advise
09-16-2014, 04:50 AM
#16
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What you describe is a brake failure, I'd just like to hear the final verdict on what caused it. What you've been told so far doesn't jive.
Unintended acceleration is a different problem. Usually caused by Toyota drivers that wedge their floor mats under the gas pedal, or confused audi drivers that hit the gas pedal instead of the brake.
Provided you have a functioning brake system, the brakes will always overpower the engine and bring you to a stop. That changes when a panicked driver pumps the brakes, eventually overheating them.
While it is possible that there could be a mechanical failure leading to a stuck throttle, or a true unintended acceleration event, nearly every case in recent years have been due to driver error.
Unintended acceleration is a different problem. Usually caused by Toyota drivers that wedge their floor mats under the gas pedal, or confused audi drivers that hit the gas pedal instead of the brake.
Provided you have a functioning brake system, the brakes will always overpower the engine and bring you to a stop. That changes when a panicked driver pumps the brakes, eventually overheating them.
While it is possible that there could be a mechanical failure leading to a stuck throttle, or a true unintended acceleration event, nearly every case in recent years have been due to driver error.
Easy to blame the driver which is what porsche did in this situation. Till you are the one they are pointing the finger at and you know what you have done.
09-16-2014, 03:23 PM
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Sorry, i dont mean to sound uncaring about all your opinions, but i am getting a little frustrated with the situation which has been going on for about 6 weeks now. Apologies to all and keep your great comments coming.
I will be changing my brake fluid again just to rule that out. Thanks guys for that suggestion.
I will be changing my brake fluid again just to rule that out. Thanks guys for that suggestion.
09-16-2014, 09:03 PM
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I have finally gotten the answer from Porsche and the dealer. They basically/indirectly said that the yaw sensor can cause total brake failure. And that replacing the yaw sensor has fixed my brake loss problem according to the info on the reciept and they stand by the fix.
While this is perhaps ok news for me and my car, it is perhaps not too good news for anyone with a porsche cayenne of this generation.
While this is perhaps ok news for me and my car, it is perhaps not too good news for anyone with a porsche cayenne of this generation.
09-18-2014, 05:12 PM
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I just got my brake fluid changed at an independent shop that only repairs Porsches. He scoped the car and is agreement with the dealers diagnosis concerning the yaw sensor as a potential cause of the brake failure. His explanation about the yaw sensor actually makes sense to me.
According to him "The yaw sensor does control the ABS. When you disable and remove the yaw sensor, the ABS brakes cannot be controlled by something that is not there. However, when a sensor that signals the ABS goes bad, in some rare circumstances, the loss of brakes can occur. The bad sensor is still sending signals to the ABS, and it may not the signals you expect."
Hope this helps clarify some of the comments from earlier. Thanks for all comments.
PS: i have a brake fluid tester and my brake fluid before the change shows normal. But i changed the fluid anyway.
According to him "The yaw sensor does control the ABS. When you disable and remove the yaw sensor, the ABS brakes cannot be controlled by something that is not there. However, when a sensor that signals the ABS goes bad, in some rare circumstances, the loss of brakes can occur. The bad sensor is still sending signals to the ABS, and it may not the signals you expect."
Hope this helps clarify some of the comments from earlier. Thanks for all comments.
PS: i have a brake fluid tester and my brake fluid before the change shows normal. But i changed the fluid anyway.
