What would cause the check engine light to stay on a 1996 Geo Tracker and the code to say EGR flow low?

What would cause the check engine light to stay on a 1996 Geo Tracker and the code to say EGR flow low?
Check out this page

http://www.asashop.org/autoinc/feb2005/techtips.htm

I have been having the same problem. Although I have not been able to fix it yet I believe the answerer is hidden somewhere in the information on that pageanother place to look is here

http://www.automotiveforums.com/vbulletin/t488839.html