It doesn't have a fan belt. It is transverse mounted and utilizes electric radiator fans.
http://www.ehow.com/how_4811888_fix-egr-valve-ford-focus.html
The bodies are exactly the same for those years. The door from the 01 will fit the 03.
Does not have a filter for you to change.
http://c.fixya.net/fixya20/uploads/Images/1405F0E.gif - The top diagram is for the '01 Ford Focus SPI SOHC, and the bottom one is for the DOHC Focus with the Zetec engine.
LIFT THE CLIPS AND PULL IT OUT
EVAP control system leak detected, very small leak
You pull the old one out and put the new one in. #31
po401 mean Exhaust Gas Recirculation Flow Insufficient Detected.
Trouble code P0401 means: Exhaust Gas Recirculation Malfunction
on the 01 zetec motor it is located below the alt. on the engine block.
It is the same as my '01 Focus. The schematic is here: http://www.modifiedlife.com/2001-ford-focus-car-stereo-wiring-diagram/ Basically it will tell you what color wire does what
Wilbraham Ford was born on 1880-01-01.