The 2003 Saturn ION was designed to replace the aging S-Series sedan and coupe. The Saturn ION Quad Coupe may sound a little like a contradictory model name, as coupes are normally associated with two doors, not four. All but invisible from the exterior, this coupe has small rear access doors, similar to the rear doors on extended cab pickup trucks. This unique coupe is larger than the S-Series coupe in just about every dimension, effectively increasing passenger comfort and cargo space. With just over 14 feet of trunk space, the ION Quad Coupe had the most cargo room of any car in this category in 2003.

There were initially two trim levels available, the ION 2 and the ION 3. The ION 2 has a number of innovative and attractive features, such as air conditioning with a dust/pollen filter, power door locks, a stereo with CD player, a driver-seat height adjuster and a fold-flat front passenger seat. Stepping up to the ION 3 nets a sport-tuned suspension with 16-inch alloy wheels, power windows and mirrors, fog lights, cruise control and an upgraded audio system.

Though still technically in its first generation, the Saturn ION Quad Coupe has seen several exciting upgrades since its introduction in 2003, including the introduction of the sporty Ion Red Line trim for the 2007 model year. The high-performance Red Line features 17-inch alloy wheels with high performance tires, a sport-tuned suspension, leather sport seats and much of the ION 3's standard equipment. Red Line only options include a choice of rear spoilers and a Competition Option Package that adds a limited-slip front differential, painted alloy wheels, a boost gauge and a programmable tachometer. This model provides solid handling and road grip when driving through winding curves, making it fun to drive as well as very attractive to the eye.