joe p - pro mechanic had some interesting things to say in this post. He provides advise on a different model, but same fuel injection system as yours - Bosch CIS.

Personally, I don't think it's your fuel filter. If it's plugged, it's plugged and dry gas wouldn't unplug it. The maint. manual calls for changing every 60,000 miles. I do mine once a year irregardless of mileage.

http://www.peachparts.com/shopforum/showthread.php?threadid=50161&highlight=hard+starting+when+cold