Traction Control Kicks In Too Easily

[todda]

I have a 2003 IS-300 with a 5-speed transmission. Ever since the car was new, it's been very annoying that the traction control kicks in way too easily - for example, it is impossible to start from a stop and accelerate around a corner, like making a U-turn or turning out of a driveway, without the traction control kicking in. In fact, this is very dangerous because you may be accelerating into traffic, and the car severely reduces your acceleration because it thinks you're slipping and it reduces power to the wheels.

Is this normal? I complained to the dealer when it was new, and they let me drive another one that did the same thing. Is there any way to fix it? It really seems like a defect Lexus should be responsible for fixing.

[bartkat]

That's called jacking it up. When you make a turn like that and hit the gas too hard the weight tranfers mostly to one rear wheel and the other one will try to spin. If you turn the trac off then I think you will be spinning one tire. So all you need to do is not hit the gas so hard so soon.

[SKperformance]

You probably have an lsd , depending on the package you have it will cause the lock up and setting off of the trac system.

[bartkat]

I only had that happen a couple times and that was when making a right turn at an intersection and the right rear wheel dropped into a giant pot hole, losing traction for an instant.

[todda]

That's called jacking it up. When you make a turn like that and hit the gas too hard the weight tranfers mostly to one rear wheel and the other one will try to spin. If you turn the trac off then I think you will be spinning one tire. So all you need to do is not hit the gas so hard so soon.

But no other car I've ever driven acts like this - including my wife's car and the many rental cars I've driven.

[SKperformance]

Todda please do a google search on an LSD then you will understand what is happening. It is a performance part used to improve forward traction. It is much worse for those of us in the snow belt where you have to make a choice of trac control or the engine being cut off when they need it to accelerate.

[todda]

Todda please do a google search on an LSD then you will understand what is happening. It is a performance part used to improve forward traction. It is much worse for those of us in the snow belt where you have to make a choice of trac control or the engine being cut off when they need it to accelerate.

Is it really the LSD, though? I admit that I am far from an expert in automotive drive trains (although I am an engineer), but when the car cuts power, I see the "Trac" light on the dash flash - and if I turn off the traction control using the control button, the problem does not occur. I'd think the LSD would still be in effect when I turn off traction control with that button - so this evidence seems, to me, to indicate it's the electronically-controlled traction control that is the culprit, and not the LSD.

Feel free to educate me... :-)

[SKperformance]

If your LSD was not locking up both the inner wheel and out wheel would roll at the same rotation speed. Since one is at a different speed the track comp sees it as the wheel is slipping and kicks in . It is a common issue with eh way Toyota designed the IS300 system that it always does this especially on a right turn at a light.

[bartkat]

That's called jacking it up. When you make a turn like that and hit the gas too hard the weight tranfers mostly to one rear wheel and the other one will try to spin. If you turn the trac off then I think you will be spinning one tire. So all you need to do is not hit the gas so hard so soon.

But no other car I've ever driven acts like this - including my wife's car and the many rental cars I've driven.

Are those other cars rear wheel drive?

[smooth1]

I can't say I have the problem you have listed here and I have the LSD rearend also. The only thing I can add to what Bartkat and SK have stated is you might want to try better tires? So long as the car has traction, and your not spinning the tires, the TC won't kick in. And of course don't gas it going into a U-turn, just wait till you coming out of it. I don't know how you drive, but if you say you had the result in another car then I would imagine it's not the car, but something your doing.

[bokch0y]

i have that exact same problem with my IS.

Here is what I have learned. The traction control system in the IS is not a true traction control system. With this said, it means that instead of really controlling the wheel spin/limiting wheel slip and balancing braking, what the IS traction control system does instead is cut power to the engine to slow the vehicle down and keep it from accelerating until both wheels are turning at the same speed essentially or relativiely close. Basically throttle controlled traction control.

I have an E46 330Ci with traction control, this system is a true traction control system and not controlled by engine throttle. The system in my E46 really does transfer and control wheel spin without cutting the engine throttle to limit speed until control is regained. I've taken corners in both my IS and E46, same speed same everything...the IS one cuts the engine throttle once it picks up un-even wheel spin, at which time you have to let up on the gas and wait until the wheels are spinning at the same grip and speed. The E46, I can just rip around the corner and keep my foot on the gas and watch the speed go up. but at the same time the light may flash and that means it's controlling the braking and re-distributing power to the tire yet it does not cut throttle so i can keep the speed and power i have to complete the turn.

Make sense?