Loss of power during spin/ fishtail
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Loss of power during spin/ fishtail
Loss of power during spin/ fishtail
2005 Carrera 997 S
Today after AutoX I stayed in the empty lot and decided to mess around a bit. It was raining and the lot was wet and slick so I wanted to push limits and learn something.
I had sport suspension engaged and PSM off.
I noticed that on hard acceleration during a turn when the rear began to hang out I lost power. I began to do it purposefully to figure out what was going on. I noticed that when the rear really started to swing out and I hammered the accelerator - trying to purposefully counter the fish tail with adding power - that the car dropped the revs. It was almost as if there was some safety feature kicking in that was not allowing me to add power during a spin. Note that I had the PSM OFF. I cannot understand why I could not power my way out of the spin - it just would not let me. It was not a fluke because I was able to consistently replicate it. It almost FELT like there was not enough fuel getting the engine during the spin. I was hammering the gas and it just would not respond almost like it wanted to stall but it was not that bad.
Is there some safety/fail-safe feature that I don't know about or do I perhaps have an issue.
Now here is a little tid-bit that may or may not be related. A month ago I was also on the AutoX track and I noticed a few times that also during hard cornering the car hesitated (sometimes a couple of times) when I hammered the gas out of a turn. It FELT like a burp or brief stall or flood. It was suggested that I may have a crappy batch of gas (?Quicktrip?). This did NOT happen again on the track today (Chevron) - so I thought that I had solved the problem. Again - i have no idea if these issues are related but I thought it may be a clue.
Any suggestions or advice would be greatly appreciated.
2005 Carrera 997 S
Today after AutoX I stayed in the empty lot and decided to mess around a bit. It was raining and the lot was wet and slick so I wanted to push limits and learn something.
I had sport suspension engaged and PSM off.
I noticed that on hard acceleration during a turn when the rear began to hang out I lost power. I began to do it purposefully to figure out what was going on. I noticed that when the rear really started to swing out and I hammered the accelerator - trying to purposefully counter the fish tail with adding power - that the car dropped the revs. It was almost as if there was some safety feature kicking in that was not allowing me to add power during a spin. Note that I had the PSM OFF. I cannot understand why I could not power my way out of the spin - it just would not let me. It was not a fluke because I was able to consistently replicate it. It almost FELT like there was not enough fuel getting the engine during the spin. I was hammering the gas and it just would not respond almost like it wanted to stall but it was not that bad.
Is there some safety/fail-safe feature that I don't know about or do I perhaps have an issue.
Now here is a little tid-bit that may or may not be related. A month ago I was also on the AutoX track and I noticed a few times that also during hard cornering the car hesitated (sometimes a couple of times) when I hammered the gas out of a turn. It FELT like a burp or brief stall or flood. It was suggested that I may have a crappy batch of gas (?Quicktrip?). This did NOT happen again on the track today (Chevron) - so I thought that I had solved the problem. Again - i have no idea if these issues are related but I thought it may be a clue.
Any suggestions or advice would be greatly appreciated.
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i have read that even if you turn the PSM OFF the car still has some level of intervention. What you are describing i have felt with PSM On. i never turn it off even when i Autox... I stil manage to be in the top ten fastest cars even in Raw Time not just PAX...
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slate, I'm a bit puzzled with your problem. I just finished a wet autox last weekend and had no issues with nannies kicking with psm off. My car was a joy to drive, was very predictable sliding on entry and exit...got 3rd fastest time of day on my 888's. I remember reading a old thread where someone had similar issue to you (doing trackdays), try doing a search. I'll let you know if I find it but I suspect its electronic issue.
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if the oil pressure shoots down drastically, as it would most likely in a spin, in a non-dry sump, do the nannies cut the power?? when i did a 180 spin at VIR last year i could have SWORN i had "both feet in" but car conked out anyway. (things happened so fast, i dont really know for sure if car conked or my left foot wasnt fast enough.)
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if the oil pressure shoots down drastically, as it would most likely in a spin, in a non-dry sump, do the nannies cut the power?? when i did a 180 spin at VIR last year i could have SWORN i had "both feet in" but car conked out anyway. (things happened so fast, i dont really know for sure if car conked or my left foot wasnt fast enough.)
Last edited by SlateC2S; Apr 15, 2013 at 04:06 PM.
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Just to be clear - there was no braking (on my part) during the spin. On the contrary, I was trying to bring the car back into line with throttle.
I am disappointed by what I am understanding from other forum posts about PSM still lurking in the background when in OFF mode and kicks in under extreme circumstances. I just find it hard to believe that Porsche has restricted the ability to completely turn off stability management.
I found these videos on youtube of 997's drifting nicely. I was NOT able to throttle through the slide AT ALL like these video show. As soon as the car significantly kicked out, throttle was cut back- which is great....if I wanted a babysitter.
Some possible suggestions include: faulty PSM, oil pressure drop (faulty), fuel pressure drop. Still waiting for some solid technical facts.
http://www.streetfire.net/video/porsche-997-gt3-donutburnout_2083611.htm
I am disappointed by what I am understanding from other forum posts about PSM still lurking in the background when in OFF mode and kicks in under extreme circumstances. I just find it hard to believe that Porsche has restricted the ability to completely turn off stability management.
I found these videos on youtube of 997's drifting nicely. I was NOT able to throttle through the slide AT ALL like these video show. As soon as the car significantly kicked out, throttle was cut back- which is great....if I wanted a babysitter.
Some possible suggestions include: faulty PSM, oil pressure drop (faulty), fuel pressure drop. Still waiting for some solid technical facts.
http://www.streetfire.net/video/porsche-997-gt3-donutburnout_2083611.htm
Last edited by SlateC2S; Apr 17, 2013 at 12:58 AM.
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