A method is provided for determining variance of actual engine torque from reported engine torque, including configuring a controller with an algorithm to calculate the ratios of current and maximum engine torque to reported torque upon the initiation of high-throttle 1-2 shift, high-throttle 2-3 shift, high-throttle torque converter lockup, and at maximum Engine Rating Torque Function for each high-throttle torque converter drive cycle. An apparatus is also provided for detecting engine torque variance in a vehicle having an engine, a throttle, and a torque converter, the apparatus comprising a controller with memory and an algorithm for calculating the maximum and current engine torque variance upon the occurrence a predetermined throttle condition, and storing the values in accessible memory, wherein the controller is configured to initiate the algorithm upon the occurrence of one of the throttle conditions, and wherein the throttle and torque converter each communicate speed signals to the controller.