Nothing horrifically wrong with these.
The top image is 1/100 which is much slower than i would expect to get consistent results. try 1/250 or 1/200 to start with.
Make sure you have 1 AF point set, as opposed to a group of them, otherwise it could be focusing on the back of the car or a tree in a back ground etc....
Once you have selected this AF point as the car comes to the corner, take the first stage of the shutter release (so the camera is auto focusing on the car) get the AF point (which should now be lit up red) on a certain point in the car (if your doing a perfectly side on pan, which is the easiest) then hold the AF point on the door handle or something. Take a burst of shots whilst trying very hard to keep this AF point constantly on the door handle. This makes sure that your panning at the right speed, even if only 1 out of 5 images is correct.
Also use shutter priority not aperture. and for stationary or head on use 1/320.
And i notice your using single shots, i would use High speed multi.
Thats my 2p's worth.