2001 Volkswagen Beetle Rough idle

2001 VOLKSWAGEN BEETLE
105,000 MILES • 4 CYL • 2WD • MANUAL
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AXELAB_Q
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  • 1 POST
Car idles rough upon start. Checked codes and my system is rich. MAF and O2 sensors seem to be fine. I was thinking I may need to change out the fuel filter. Sound like a good idea? Any suggestions? I'd appreciate the help.
Apr 16, 2010 at 7:37 AM
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RASMATAZ
  • ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Probable causes of an engine running rich are as follows:

1.Fuel pressure not within specs.Can be cause by restricted fuel return line or defective fuel pressure regulator.
2.Defective Oxygen Sensors.
3.Leaking injectors.
4.Coolant temperature sensor out of calibration.
5.Restricted air intake system.
Apr 16, 2010 at 4:25 PM
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