You may want to make 100% sure you have the correct MAF. They all look pretty much the same but their sensor characteristics have to be matched to you particular car. The 2000 year is a cross over year.
This is from the Pelican DIY article. Link here
Porsche Boxster Mass Air Flow Sensor (MAF) Replacement and Troubleshooting - 986 / 987 (1997-08) - Pelican Parts Technical Article
Porsche Part # BOSCH Part # Application Notes
996.606.123.00 0-280-217-007 1997-99 All Boxsters Sensor for use with cable throttle cars
996.606.124.00 0-280-218-009 Early 2000 Boxster / Boxster S Original sensor for E-gas cars
(thru Boxster 2.7L Chassis #98 6YS 62 0414 and #98 0YU 62 5099)
(thru Boxster S 3.2L Chassis #98 0YS 66 0257 and #98 3YU 66 2413)
986.606.125.00 Mid 2000-04 Boxster / Boxster S First updated sensor for E-gas cars
(discontinued and replaced with version 125.01 below)
986.606.125.01 0-280-218-055 Mid 2000-04 Boxster / Boxster S Latest updated sensor
987.606.125.00 0-280-218-145 2005- All Boxster / Cayman Integrated housing design