There's two common things to consider but I'm not clear on the symptom. The common one is when you turn either way, then the steering wheel doesn't come back to centered on its own, AND the car keeps going in the direction the steering wheel is turned until you pull the wheel back to centered. That's called "memory steer".
The less-common symptom is when the car goes straight down the road after turning and letting go of the steering wheel, but the steering wheel is no longer in the same position. At first that might be the only symptom, but as the cause gets worse, something will shift even while you're driving straight and hitting normal small bumps in the road. That's called "steering wander" and makes for a really miserable car to drive.
What you described could apply to either of these conditions. Memory steer is caused by a binding upper strut mount or less often, a tight ball joint. If your steering wheel is in a different position after making a turn, it's usually because the rack and pinion steering gear is loose and is sliding back and forth on its mounts. That can be due to loose bolts or worn rubber isolators. You should hear and feel clunking associated with that too. Dangerously worn steering and suspension parts can cause a changing steering wheel position, but something would have broken long before it could get bad enough to cause the wheel to be off half a turn.
Sunday, October 19th, 2014 AT 8:48 PM