The top speed of a 1998 Dodge Avenger with a 4-cylinder engine depends on several factors including the specific engine (there were a couple of different 4-cylinder options offered that year), the vehicle's condition (tire pressure, overall maintenance), and even things like wind resistance and road conditions.
However, a reasonable estimate for the top speed would be in the range of 85-100 mph. It's unlikely to exceed 100 mph, and under ideal conditions, it might reach the higher end of that range. But that's a theoretical maximum; it's not safe or recommended to push the car to its absolute limit.
