engine light on on 2004 Cadillac CTS

accoring to the computer it showed that the problem was coil,injectors **both have been changed and new spark plugs have been changed also and still have the same problem

Asked by for the 2004 Cadillac CTS
Here are some of the problems that can cause a cylinder misfire:

Worn out Spark Plugs Ignition Wires, Coil(s), Distributor Cap and Rotor (when applicable)
Incorrect Ignition Timing
Vacuum Leak(s)
Low or Weak Fuel Pressure
Improperly functioning EGR System
Defective Mass Air Flow Sensor
Defective Crankshaft and/or Camshaft Sensor
Defective Throttle Position Sensor
Mechanical Engine Problems i.e Low Compression, Leaking Head Gasket(s) or Valve Problems