Could be running too rich due to the follwoing below:
1. Excessive fuel pressure can be cause by restricted fuel return line
2. Defective Oxygen Sensors.
3. Leaking injectors and fuel pressure regulator.
4. Coolant temperature sensor out of calibration.
5. Restricted air intake system.
6. Leak in the Evap system
Sunday, February 20th, 2011 AT 5:45 PM