From a standstill, I accelerate gently sometimes a little less and suddenly the front end vibrates and the Traction Control indicator lights up on the cluster.

Does this 75% of the time. It goes away once I continue to accelerate but I am able to increase the length of the shutter by go very slow.

The car seems to loose power and it feels like it is about to die. Perhaps the sensor is bad?

Thanks guys...

 

The symptoms you list are perfectly normal for engagement of the Trac control. The system is designed to compare the rotation of your right and left (front) wheels by looking at the ABS sensors. If one wheel is rotating significantly faster, the system will apply the brake to that wheel - using the ABS system to "pulse" the brake rapidly, slowing that wheel and keeping it from robbing power from the opposite wheel. This would account for the noise, shuddering, and the Trac light coming on . . . even the engine slowing up as the ECU starts rolling off the power.

In your case Trac seems to be engaging for no reason IF you are not experiencing wheelspin that would set off this feature. You are correct, it would seem the problem may be sensor related.

At this point my diagnosis, like yours, starts sucking air. Anyone have a similar experience?

 

are you in snow? spinning tires?
check engine light on?

 

No snow.
Dry road conditions.
No Check engine Light.

 

Tire condition and air pressure needs to be checked. With FWD, even at 128k miles, (with new tires), I experience this fairly often. [Obviously loose gravel at street junction aggravates the situation ... no snow in central Texas]

Fix is buy better tires or gentle use of the pedal.

Salim

 

without experiencing this myself, i really can't diagnose it further. i would go to lexus and pay them an hour labor to scan your codes in you abs/tcs module.

 

I have posted this remedy once before here on the board,but i cant find it.the traction control uses the antlock brake sensors,you need to clean the sensors on each wheel hub,with Wd-40 front real easy,10mm bolt. Rear, a little more diffacult to get the sensor out.(I never did get my r/r sensor out) What happens is,the sensors build up fine metal particles,due to sensor being a magnet.Clean each one real well,reinstall,and should solve your problem.I helped someone elese on this board,and it worked for him as well.(same symptoms)

 

https://www.clublexus.com/forums/sho...d.php?t=285023

I plan to clean these next Saturday.

 

might not hurt to give them a good cleaning lex.

 

Nothing wrong in keep the sensors all clean, but with accumulation of debris, the ABS /trac will be less sensitive. The stuttering would be when the trac system would be hyper-sensitive.

Salim