Johnny Rad

How does VSA work?

It was raining cats and dogs this afternoon and I was pulling out of a driveway onto the road. As I waited for my turn, I had my front driver side wheel in the concave gutter and my front passenger side wheel a few feet before the gutter. I spot my chance and gun it ... lots of wheel spin for a second, but no forward progress. I eased off the loud pedal and the car made its way forward finally. It felt as if my front driver side wheel was the culprit, but it might have been both.

Apparently, VSA doesn't re-route power to the wheel with traction. Instead, it channels it to the one that is spinning?!

Please educate me on VSA.

typeR

it doesnt do either...the open differential in your transmission does the power rerouting you spoke of...the VSA has two main functions...cuts throttle during straight line acceleration envolving wheel spin...and it may also cut throttle while applying break to any one or more wheel trying to correct a yaw condition that could result in an out of control spin

loulinjai

i live in calgary where theres black ice like 4 months of the year, so basically i see the light go on everyday for a good chunk of the year. Im not exactly sure how vsa works, but im know theres a computer and a pump for basics. it depends on the level of wheel spin you have, and the pump reroutes power to the wheel with more traction according...in a pulse (kinda like abs, but a little different). on corners, if the yaw control (wheel input does not equal g force measurements), then it brakes the front wheel until its back on the intended track (if ur foot isn't on the gas), or cuts torque to either wheel (if ur foot is on the gas). it really is a nice system to have, it beats most of the other stability control systems out there.

Johnny Rad

OK. It sounds like it's not so much a traction control unit, but rather an "oh shit" averter. Yes / no?!

power3dfx

it prevents wheelspin, any front wheelspin. that is all it does as far as straight line. in your situation, it allowed some spin and then cut power.
and yes it is more of an oh shit averter, but only when you have some speed and are cornering. otherwise it is a good feature for accelerating in bad conditions.
if you were to keep the pedal to the floor, it would have spun, tcs comes on, you spin a little more, it comes on again, until you finally stop spinning.