Every once in a while I'll have the car pull to the right or left - not terribly hard to the point that it pulls the wheel out of my hand or is dangerous, but noticeable. It seems to happen when coming to a stop, and if there is a slight left or right grade to the road, dip, bump, or other disturbance. It seems to continue to pull until I come to a complete stop, then doesn't happen again. It does not happen at other times during braking, turning, etc.

I've been wondering if this might be related to the EPS system seeing a shift in the wheels to right or left, mis-interpreting this as driver input, and trying to apply some "assist" inappropriately?

This leads to a more academic question: how does the EPS system tell the difference between torque applied to the steering wheel by the driver vs. torque created due to forces on the wheels and then transmitted up through the steering linkage?

-Matt

 

Assuming that your tire pressures are all good, I think what you are experiencing is a phenomenon called "Tramlining", where the tires will follow ruts & hollows in the road, cracks and irregularities. This is accentuated by braking. Tramlining is not an uncommon occurance in cars that have relatively wide tires for their size.

I'm not an expert on the EPS, but I don't think it can tell the difference between the force applied at the steering wheel and force applied by the ground at the front wheels. EPS works in relation to vehicle road speed in conjunction with how much you turn the steering wheel. The most "power assist" comes at low "parking lot" speeds and at higher speeds, the assist decreases.