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So i took my car to a track day over the weekend and I was experimenting a few laps with my tracktion control on and off. A few laps of each. So I finished the first session with the Trac on. Then I started the second session with it on then turned it off after a few laps. Heres what happend:

Session 1:
The first few laps with the trac on I only noticed a few times the power was cut. First time was into an accelerating first turn then at the end after heavy braking, a fast turn and then hard accel. My last lap on my first session I noticed the trac light blinking longer and cutting power longer than it seemed to before.

Session 2:
I started out with the trac on and took to the course right off the bat on the first turn the power was cut and the trac light was blinking the whole time. Then on the hard brake quick turn I lost power into the accelrating out. Soon people started passing me out of turns as my power was lost. I only put up with this for one more lap and it seemed my power was cut at ever hard turn and accelration. The trac light seemed to be blinking for ever. My instructor mentioned this could be due to the brake and tires heating up. But I wasnt sure. So I finsished the course with the trac off.

So here's the question, does the traction control respond to when its been activated a lot to become more aggressive in cutting back the power? Is our traction control a learning computer?
 

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I don't think so, but what I have noticed is that the TC is very sensitive.

Even during normal braking on bumpy roads, it will kick in.

What I have noticed during the winter is that when you keep TC on (I have a manual tranny), and the TC kicks in, if for some reason you stay on the gas and break traction again, the TC will never disengage. I've confirmed this a few times in the dry as well. In order FOR ME to disengage the TC, I have to let off the gas pedal until the light stops blinking.

If you stay on the gas after the light begins to blink, it won't seem to release for me. I'm guessing that once you engaged the TC, you got back on the gas, only to engage the TC again at the next corner. In between the to corners, you were on the gas, which never allowed the TC to stop cutting power.

In my opinion, our TC is WAY too sensitive. I almost never use it. Even in chicago winters I very rarely use it.
 

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Its not a learning system, it just uses several variables to determine how much to cut throttle and for how long.
 

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Not sure why you would want to run on track with the traction control on. If you're trying to learn how the car handles you should do it without interferance from other inputs. Your sense of self preservation will keep you from getting too crazy. Your instructor won't push you over the edge either.

BTW, if you're gonna run with the trac on check your rear brake pads. They will get worn out pretty quickly.
 

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Not sure why you would want to run on track with the traction control on. If you're trying to learn how the car handles you should do it without interferance from other inputs. Your sense of self preservation will keep you from getting too crazy. Your instructor won't push you over the edge either.

BTW, if you're gonna run with the trac on check your rear brake pads. They will get worn out pretty quickly.
why would the rear brake pads wear out? I dont think that the IS300's trac system uses brake modulation. It has no brake pump in its abs block. When the IS looses traction, it cuts timing and retards the timing. Thats why it feels almost like you hit a freight train.
 

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why would the rear brake pads wear out? I dont think that the IS300's trac system uses brake modulation. It has no brake pump in its abs block. When the IS looses traction, it cuts timing and retards the timing. Thats why it feels almost like you hit a freight train.
It's a combination of systems working together. Get the car loose with a little roll in a turn (doesnt need to be power over). The settling of the car is controlled with the brakes. The reduction of power is controlled by the engine. Also note that he mentioned that this was happening under braking as well. ;)

Have you ever driven with the trac on and felt the car hunker down then go where the wheel is pointed? The engine alone won't do that. ;)
 

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It never went where the wheel was pointed with trac on.;)
It pushed and pushed, then trac killed the power to the engine.
 

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Your car didn't squat & line up?

When I've used the trac control I've experienced the car settling & slowing mid turn and I'd go though rear pads twice as fast.
 

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Its not learning, but you are.

You are more aware of what sets it off and how you can work around it.

All the bitching about trac control and i barely if ever set it off
 

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It never went where the wheel was pointed with trac on.;)
It pushed and pushed, then trac killed the power to the engine.
Youve never driven in snow. End discussion. The ABS cycles HEAVILY in snow. I've heard it on wet pavement too....
 

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well today's lesson class is don't go out to the track with TRAC activated. You're out on a course to learn how to drive your car. TRAC is there for those who do not know how to drive their car.

also, our system is not "learning" the same variables will pretty much activate it. and it rarely disengages if your foot remains on the gas pedal.
 

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our trac system does not use the brakes to control the cars traction. nor does it pull/retard timing. it simply closes the throttle plate, when it detects loss of traction, in turn cutting the engines power, until it thinks the car regains traction, the it goes back to the desired input from the gas pedal.

the VSC on newer IS's uses brake modulation to keep the car on the driver's theoretically intended path.
 

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our trac system does not use the brakes to control the cars traction. nor does it pull/retard timing. it simply closes the throttle plate, when it detects loss of traction, in turn cutting the engines power, until it thinks the car regains traction, the it goes back to the desired input from the gas pedal.

the VSC on newer IS's uses brake modulation to keep the car on the driver's theoretically intended path.
If that were true then you car would begin to accelerate again if you simply left your foot on the throttle once it engages and stops the slip. It doesn't allow you to do that until you have lifted off the throttle.

With Trac on: Once the the wheel speed & other sensors detect a difference greater than programmed as "ok" the DWB backs the throttle off, brakes are modulated depending on what the computer thinks is neccisary, the little light in the dash winks at you and I'm not sure how much truth there is to the ignition retard during all of this. Also, if you have an auto it unlocks the torque converter.
 

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our trac system does not use the brakes to control the cars traction. nor does it pull/retard timing. it simply closes the throttle plate, when it detects loss of traction, in turn cutting the engines power, until it thinks the car regains traction, the it goes back to the desired input from the gas pedal.

the VSC on newer IS's uses brake modulation to keep the car on the driver's theoretically intended path.
See my above post about snow.....next time it rains in your area go to a parking lot and try to drift around in first gear with TRAC on, you hear that grinding? Thats the ABS pump working your brakes! holy crap!
 

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See my above post about snow.....next time it rains in your area go to a parking lot and try to drift around in first gear with TRAC on, you hear that grinding? Thats the ABS pump working your brakes! holy crap!
Question, do you have VSC? I did not have VSC. Never heard the ABS pump pumping. (In the rain).
 

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Hmmm, I've heard the ABS pump before, got a manual though.
 

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BZZZZT!!! Grind grind grind grind.....Those are the noises it makes....especially when the "Snow" button is on, it pulls less throttle, reduces throttle response and power, allows more slip, and cycles ABS more heavily. Yes i have heard the ABS cycle with out snow activated too. It just pulls throttle WAY more...almost kills it on ice or snow
 
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