Threxx

I looked in the owners manual and all I got was a poorly translated description of what conditions I should use each setting for... but it never really said what specifically the car did with each setting. So could someone fill me in?

I'm going to guess that the "SNOW" setting makes the traction control system hyperactive?

Also, what is "VSC"? I assume it stands for Vehicle Stability Control like it does on some other cars I've seen... but what specifically does it do to stabilize the car and when will it do this? Is it also hyperactive when the car is set for "snow"?

What does the "power" setting do? Does it make the tranny shift harder or maybe lets the engine rev higher before it shifts when at partial throttle? Does it make the traction control or vehicle stability control any more aggressive for maybe less aggressive?

And pending the answer to the aforementioned questions... is there any way to turn off traction control? Is that what "VSC OFF" does for me? I don't necessarily want to turn off the function that keeps me from running off the road... I just want to be able to launch without the car getting overly paranoid and cutting my throttle back significantly. I've found that in most cars, a decent driver can launch harder than any traction control system will. Is this true with the GS4?

And also, this is way off-topic from the rest of the questions... but is the throttle control electronic in a 99 GS400? Or is there an actual throttle cable running from the gas pedal to the upper intake\butterfly valve? I would just check for myself but the cover is on the motor and I haven't had a chance to take it off yet.

Thanks!

///MDex

ECT: Electronically Controlled Transmission

SNOW: reduces torque so your wheels spin less, and hopefully allow more traction

PWR: holds the transmission to higher RPMs in each gear to achieve greater power delivery

VSC OFF: removes the 'safety net' so to speak; disables Traction Control; allows the wheels to spin; with it ON, the system will modulate the ABS and throttle to bring the car back under control should the wheels break loose; the car will still beep at you when it senses YAW; most of us that went on the Deal's Gap / DragonTail Meet know this.

That's the quick and dirty off the top of my head. HTH

TXLeXTC

As for which to use, I was reccomended by a Lex Tech to leave the tranny in POWER mode, as long as you dont mind a slightly harder shift, as it is better for the tranny over the long haul.

VSC is good for getting you stuck! Here is my experience with VSC. Not once have I had it save my ***. A NUMBER of times it has caused me pain tho. Normally when I am making a turn out onto the highway feeder road at peak hours i have to really jump on it, then the wheels slip, then it seems to just kill my power for a few seconds. That will scare the crap outta you when a truck is coming up on your rear quick. Then it got me nice and stuck when my wheels started slipping while driving out onto the beach. Given, a GS is not an offroad vehicle, but there were plenty of cars out there, the VSC just killed me. Once I got pulled out and turned it off, no probs.

I just wish the vsc was A) like the tranny control so that you turn it off, and leave it off and B) had a green indicator light, the amber always catches my eye too much....

mooretorque

Dex is correct; also starts in 2nd gear, for reduced gear-multipled torque to attempt to prevent wheelspin. Don't think it changes the VSC mapping, though.

As Dex said plus will downshift sooner/less accelerator pressure. Again, no effect on VSC. Also, no perceptible change in the speed of the shifts.

If you're running in a straight line, I'd agree; turn off VSC to allow more wheelspin at launch. ( And I do wish it were less aggressive in it's intrusion when it's on. It really does bog things down at inopportune times. ) But if you're doing anything other than dragracing, I'd leave it on, unless you are supremely confident in your ability to keep it out of the weeds. And even then............

All GS models are drive-by-wire.

theanimala

Snow does more then start in second gear. Drive with the snow button on and give it half gas. The car will accelerate like a yugo. Then turn off the snow mode. The car will instantly have more power, WITHOUT dropping a gear. I believe snow mode cuts the power by at least 50% in any given gear.

GJSGS4

This has been discussed before, but "snow mode" does not make the transmission start in 2nd gear. At least not on a '99 GS4. You get the same number of shifts in snow, normal and power modes. Try it yourself. The snow mode definately makes the throttle less sensitive. In snow mode the first 50% of pedal depression is like 10% in normal mode. Maybe ECT should stand for Electronically Controlled Throttle.


Yes, the throttle control is electronic on a '99 GS4. There is still a throttle cable running up to the intake. The cable operates a position sensor that gives an input to the electronics. The electronics control a servo motor that positions the intake butterfly. If the servo or ellectronics fail the butterfly valve arm will fall against a stop and be operated by the cable. Giving the car a fail safe throttle.

bitkahuna

iTrader: (20)

I think you're right! Check this...

http://pressroom.toyota.com/mediakit...techchart.html

I thought you were wrong when I first read the following article but it's about the RX300 which is consistent with the chart at the link above.

http://www.autorevista.com/articles/99rx300.htm

"Snow mode starts off the vehicle in second gear".

mooretorque

I once again stand corrected. That's what happens when you have an RX (which I drive when it snows) and a GS (which I don't).