The SL2 Engine

• The Saturn SL2 is equipped with a 1.9-liter DOHC (dual overhead cam), 16-valve, in-line, four-cylinder engine. It runs on 87-octane gasoline and is capable of producing 125 horsepower at 5,600 rpm and 122 foot-pounds of torque at 4,800 rpm.
  
  

Typical Firing Order

• The typical firing order sequence for a four-cylinder engine is as follows: 1 3 4 2 or 1 2 4 3 or 1 4 3 2. The typical firing order sequence for a five-cylinder engine is 1 2 4 5 3. The firing order sequence for a six-cylinder engine is typically 1 5 3 6 2 4, 1 2 4 6 5 3, 1 4 2 6 3 5 or 1 4 5 6 3 2. For an eight-cylinder engine, the typical firing sequence is 1 6 2 5 8 3 7 4, 1 3 6 8 4 2 7 5, 1 4 7 3 8 5 2 6, 1 3 2 5 8 6 7 4.
  
  

SL2 Firing Order

• The standard engine in the Saturn SL2 uses the most common firing order for an in-line, four-cylinder engine -- 1 3 4 2. This means the first and third cylinders fire together, followed by the second and fourth cylinders firing together. While this is true for many four-cylinder engines, not all have the same firing order and not all engines necessarily fire more than one cylinder at the same time.