This paper proposes and evaluates methods for measuring the driving capability of a robotic driver for automotive emissions testing.In order to evaluate driving capabilities, variables such as actual speed, intake manifold pressure, accelerator pedal position, brake pedal position, and others are measured while the driver repeats a specific speed pattern. The values of the data between successive runs are statically analyzed to determine what is referred to as the residual deviation. The residual deviation is then used as an “index of repeatability” to evaluate the repeatability of emissions tests results. Additionally, the relationship between target speed and actual speed among runs is evaluated using similar techniques to generate an “index of traceability.”Tests were run on several drivers. The “index of traceability” and “index of repeatability” obtained from these tests were found to have expressed the repeatability of the emissions test results and the traceability of target speed very well.Since a good emissions tests driver will generate consistent results between runs of the same speed pattern, a good test of a drivers ability is one that measures his consistency. This suggests that using residual deviation is an effective measure of the abilities of emissions test drivers.