Is my Stability Control Overactive?
#16
#17
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The only time my car has behaved that way was when I had an out-of-spec diameter tire in the rear, or if I noticeably mismatched wear/grippiness in front vs rear. I gather you do not have those situations in play here, but the symptom you described is exactly what happens when my car has either of those going on.
#18
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The only time my car has behaved that way was when I had an out-of-spec diameter tire in the rear, or if I noticeably mismatched wear/grippiness in front vs rear. I gather you do not have those situations in play here, but the symptom you described is exactly what happens when my car has either of those going on.
#19
#20
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Mismatched tires is a big no no. Different compound, grip levels, sidewall stiffness...its a wonder you have not crashed yet. I have Ventus V12 all around on my 09 C4S, and they can squirm quite a bit, but all four do it at the same rate. The Bridgestone fronts will not work with the Ventus rears.
#21
Drifting
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Old out of date concrete compound tires.
More that 3 ish years old? Get hard.
8-9 years old? Silly.
Santa delivers to your house this very month. Put four on your list.
More that 3 ish years old? Get hard.
8-9 years old? Silly.
Santa delivers to your house this very month. Put four on your list.
#23
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I mean the the front tires were oem Bridgestone not the original tires. The car has 43k miles and the tires has over 70% tread left. I doubt they are the original tires.
after thinking about it some more, I don't think it's the psm but rather the abs that's kicking in, or at least that's what it feels like.
Its just frustrating because I'm no where near the limit when it kicks in. Abs works fine in a straight line. The pulsitating pedal only happens when in a curve. Guess I need to take a trip to the dealer.
after thinking about it some more, I don't think it's the psm but rather the abs that's kicking in, or at least that's what it feels like.
Its just frustrating because I'm no where near the limit when it kicks in. Abs works fine in a straight line. The pulsitating pedal only happens when in a curve. Guess I need to take a trip to the dealer.
#24
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The PSM is essentially the ABS activating when things aren't smooth in the corner. The PSM system will actuate the ABS system on whatever wheel will correct the problem. If I were you I would just go get 4 new tires and be happy knowing you have new shoes that will last you a awhile without second guessing how old they are. Mis Matched tires on these cars is a bad idea as other have said. I'd be hesitant to turn the PSM off. If it's kicking in that means sometheing is wrong and by turning it off, you're eliminating a feature that could save you from getting out of control.
#25
Drifting
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Mismatched tires is a big no no. Different compound, grip levels, sidewall stiffness...its a wonder you have not crashed yet. I have Ventus V12 all around on my 09 C4S, and they can squirm quite a bit, but all four do it at the same rate. The Bridgestone fronts will not work with the Ventus rears.
I have driven several cars with different brands of performance tires front/back, including my Porsche. When you drive a car that goes through rear tires at twice the rate as the fronts, it just happens.
If driving a Porsche with two different brands of tires puts someone in a ditch, that driver doesn't need to be in charge of anything more powerful than a Hoverround scooter.
#26
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if you are commuting or puttering around sure go ahead and mismatch brands. If you are driving aggressively or at the track, then not such a good idea. I have Ventus V12, they squirm....Bridgestones are stiffer, I've had them in the past. Squirm back and firm up front, not good and the ECU and ABS and TC is not programmed to handle that either. If he wadds it so be it.
#27
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Are you canyon carving? Are the roads highly trafficked? I found that So Cal roads get dusty/sandy quick if they haven't been trafficked much. So if you're hard braking through a corner on even a slightly dusty road, then yes PSM with activate ABS to add understeer and keep the rear from swapping ends.
You can drive a corvette like that but not a 911.
You can drive a corvette like that but not a 911.
#28
Drifting
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if you are commuting or puttering around sure go ahead and mismatch brands. If you are driving aggressively or at the track, then not such a good idea. I have Ventus V12, they squirm....Bridgestones are stiffer, I've had them in the past. Squirm back and firm up front, not good and the ECU and ABS and TC is not programmed to handle that either. If he wadds it so be it.
Also, the levels of grip at the front and back are always different anyway. You have over 2 inches more tread width on the ground in the back with the rears loaded much more than the fronts, different sidewall heights and you have to consider that the rears wear out twice as fast as the fronts, making the depth of tread different at all times. This makes the two ends of the car completely different, even with the same brand of tire at all four corners.
The traction control is programmed to react to wheelspin, yaw, and a bunch of other variables but it's not particularly smart. It just constantly runs through a series of "if x then y" situations. It is completely capable of accounting for the differences between two different brands of performance tire.
#29
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I just recently got my first Porsche, a 2010 base PDK with sports chronos. I noticed that when exiting a freeway offramp with a curve (cloverleaf) at a normal speed, the brake pedal would pulsate (feels like abs) if I even lightly touch it. I am in no way going too fast, or scrubbing off too much speed. Just normal slowing down. Is this normal for the 997? Also I did not see any stability control lights light up in the dash when the brakes are pulsating. Is this normal?
For reference, I can brake much harder in my 3 series and it would not even activate the stability control.
For reference, I can brake much harder in my 3 series and it would not even activate the stability control.
P.S. I only drive in Sport mode, so not sure if it would occur in normal mode.
#30
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In my case I don't think it has to do with the different tire brand front and rear. On those off ramps I'm going maybe 2/10. I've done canyon carving and psm hasn't kicked in. Then again I'm only going maybe 5/10. Lots of blind corners on the canyon with rocks in the middle of the road where I drive.