I went through the first 3 pages after searching for VSA, and found nothing. . .

Bought the car on Sunday 4/6/14, and drove it for about 10-20 miles.

After 20 miles, on a freeway, a vibration developed in the front right of the car. The vibration got bad enough I pulled over. There was a strong smell of brake/brake dust. I let the car sit for ten minutes or so. Suspecting that the wobble was actually the VSA pulsing, I disengaged VSA, and then drove the car home (from SoCal to NorCal, 378 miles total), without any issue, including me re-engaging VSA the last 100 or so miles.

This morning is the second time I drove the car, and it is back. While I have no issue in driving around without VSA, I'd rather not.

Anything similar, known, before I take the car into the shop and have them examine the wheels, rotors, or more?

 

That is freaky. Maybe a sticking caliper since you saw there was a strong presence of brake dust and smell. The VSA light would turn on if that was the VSA kicking in. IIRC VSA doesnt apply brakes, i believe it cuts power. I could be wrong.

 

Just drove it at lunch with the VSA off, and all was well. Freaky indeed.

 

The same thing happend to me a week or so after I got my S.
I was going about 40, strong vibration coming from right front...I thought a belt shifted in the tire. I pulled over...the brakes were over heating. I let them cool for 10 min and it drove ok after that. A year later and 10k miles, problem never came up again. If you get any info let me know.

Thanks.

 

Check for any dirt/debris on the wheel speed sensor. When VSA intentionally activates the light will flash when it's active. Any other electrical issues? See if there's a ground in that area that's corroded or loose. Any rain? VSA will activate the brakes and cut engine power btw, but that could be ABS function if you were going straight. What year is your car?

 

Did the S seem to slow down as well or just vibrate?

 

VSA will both cut power and apply brakes to one or more wheels. It also lights the dash light. It will pulse the brakes, and light will pulse as well. Its very noticable. If you were driving down the highway and VSA erroneously engaged, you'd know it.

I think you just have a sticking brake caliper. There are a number of things that can cause your issue. Sticking/corroded caliper slide pins, sticking/corroded caliper piston, moisture in your brake fluid, even a bad rubber brake hose (broken on the inside, a flap of the lining acts as a one way valve).

Replace your brake fluid, and do the gravity bleed process. Remove your calipers, and polish and grease your slide pins. Inspect your rubber hoses. These are easy and cheap, and good to do anyway, and will likely solve your problem.

If still an issue after above, rebuild your calipers.

 

VSA will both cut power and apply brakes to one or more wheels. It also lights the dash light. It will pulse the brakes, and light will pulse as well. Its very noticable. If you were driving down the highway and VSA erroneously engaged, you'd know it.

I think you just have a sticking brake caliper. There are a number of things that can cause your issue. Sticking/corroded caliper slide pins, sticking/corroded caliper piston, moisture in your brake fluid, even a bad rubber brake hose (broken on the inside, a flap of the lining acts as a one way valve).

Replace your brake fluid, and do the gravity bleed process. Remove your calipers, and polish and grease your slide pins. Inspect your rubber hoses. These are easy and cheap, and good to do anyway, and will likely solve your problem.

If still an issue after above, rebuild your calipers.

 

VSA will both cut power and apply brakes to one or more wheels. It also lights the dash light. It will pulse the brakes, and light will pulse as well. Its very noticable. If you were driving down the highway and VSA erroneously engaged, you'd know it.

I think you just have a sticking brake caliper. There are a number of things that can cause your issue. Sticking/corroded caliper slide pins, sticking/corroded caliper piston, moisture in your brake fluid, even a bad rubber brake hose (broken on the inside, a flap of the lining acts as a one way valve).

Replace your brake fluid, and do the gravity bleed process. Remove your calipers, and polish and grease your slide pins. Inspect your rubber hoses. These are easy and cheap, and good to do anyway, and will likely solve your problem.

If still an issue after above, rebuild your calipers.

 

VSA will both cut power and apply brakes to one or more wheels. It also lights the dash light. It will pulse the brakes, and light will pulse as well. Its very noticable. If you were driving down the highway and VSA erroneously engaged, you'd know it.

I think you just have a sticking brake caliper. There are a number of things that can cause your issue. Sticking/corroded caliper slide pins, sticking/corroded caliper piston, moisture in your brake fluid, even a bad rubber brake hose (broken on the inside, a flap of the lining acts as a one way valve).

Replace your brake fluid, and do the gravity bleed process. Remove your calipers, and polish and grease your slide pins. Inspect your rubber hoses. These are easy and cheap, and good to do anyway, and will likely solve your problem.

If still an issue after above, rebuild your calipers.