Modeling only a HDR's camera's lens blur, noise and sensitivity is not sufficient to predict image quality. For a fuller prediction, motion blur/artifacts must be included. Automotive applications are particularly challenging for HDR motion artifacts. This paper extends a classic camera noise model to simulate motion artifacts. The motivation is to predict, visualize and evaluate the motion/lighting flicker artifacts for different image sensor readout architectures. The proposed motion artifact HDR simulator has 3 main components; a dynamic image source, a simple lens model and a line based image sensor model. The line based nature of image sensor provides an accurate simulation of how different readout strategies sample movement or flickering lights in a given scene. Two simulation studies illustrating the model's performance are presented. The first simulation compares the motion artifacts of frame sequential and line interleaved HDR readout while the second study compares the motion blur of an 8MP 1.4 mu m, 5MP 1.75 mu m and 3MP 2.2 mu m image sensors under the same illumination level. Good alignment is obtained between the expected and simulated results.