"Motor Trend"'s only complaint was the Quad 4's NVH (noise, vibration and harshness) and noted it was one of the most raucous engines of its time. Beginning in 1991, the 3.1 L V6 could be had as an option on the GTZ, but it was only available with a three-speed automatic transmission that increased the 0-to-60 mph time to around 9.0 seconds. The 3.1 L V6 was standard on 1990–1992 GT models and optional for all base models and GTs in 1992. Starting in the 1994 model year the 3.1 L V6 could only be ordered with an automatic transmission.