A virtual error microphone-based active sound quality control (VEM-ASQC) algorithm is proposed to make engine sound quality better inside a car cabin in this study. In a single-input and single-output system, if a VEM is installed at either left or right ear, the sound pressure level (SPL) at the other ear can be fluctuated, and this leads the excessive SPL difference between the two ears when previous methods were applied. In this paper, an uncomplicated method that can make engine sounds at both left and right ears track the target engine sound levels with less errors and reduces the left-right tracking error (TE) (in SPL) difference was investigated. The suggested VEM-ASQC algorithm was implemented in an actual car for real-time control experiment, and target profiles of nine engine orders were designed to control the sound quality actively. The control experiment showed that the proposed approach reduces the errors to track the target levels and the left-right TE differences more compared to those by the previous methods.