Helping a co-worker with a Z3 issue...

Good afternoon!

I am searching and not really having much luck...

A co-worker of mine is having an intermittent issue with his 2001 Z3 2.5i Auto. He says it will randomly feel like a brake caliper is grabbing and the traction control light will come on. But then it goes away just as quickly as it happens. Its a little un-nerving as the car does do a slight "jerk" when it happens. I will ask him tomorrow if any other lights come on and if he can tell which wheel is grabbing, but I wanted to at least get a thread started for suggestions on what could be causing this. They purchased this car about two years ago, used, it has less than 40,000 miles on it...

Thanks for any help!

Has he looked to see if there's anything wrong with his rotors or anything that could be caught up under there?

i would put the car on a lift and remove all 4 tires and inspect the brakes very carefully. i would look for a discolored rotor and get a good feel for all the wheel bearings. any issues with the anti lock brakes or active handling ?

The traction control light comes on when its is in use. Is this happening with the hammer down going around a turn? If so that means the indicator is working properly. If it just happens while driving normally then yea you have yourself a problem. Check the brakes and also check if the rear differential is leaking. If so the sensor is probably shot.