It means exactly what the description says it means.
The cause is carbon buildup choking off the passages in the EGR system,
resulting in impeded gas flow. The cure is to get rid of the carbon. It's
an involved and labor-intensive procedure.
Reference TSB 00-004 for technical specifics.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.