What does a diagnostic code P1401 - 401 - mean on a Ford Windstar?

Answer 1

401 indicates a problem with the EGR system.

Be sure to see "Related Questions" below for more about this system - BEFORE spending any money!
Code 1401 is a backflow fault with the EGR valve. They get dirty with buildup and stick. Part is around $60.00 It is the round, disk shaped configuration located near the firewall. It connects into the intake manifold at the bottom of the EGR valve and a line connection at the top of the EGR valve. DIY is easy as long as you spray the nut on the bottom of the fitting to the intake first to free it.

It means that your PCM has detected something wrong with your egr system. Follow along and check what applies first. your egr system is something that recycles unspent gasoline vapors back into your engine.

fixing it will improve your mileage, and make you pass an epa test!!

possible causes of insufficient flow:

• bad dpfe sensor-notorious in fords for failing, it measures the pressure of the system
• clogged tubing from valve to vacuum- very possible, they twist and turn all over the place, a piece of carbon could easily get stuck in there
• bad evr (the vacuum pump that controls the whole thing) the little motor in the vacuum could have burnt out
• bad egr valve-highly unlikely, but possible
• cracked or leaking hose-first check the ones connected to the dpfe sensor itself.
• bad pcm-uh-oh. that's pricey. but unlikely.
  

first, check the hoses. then go to autozone and get a new dpfe. 20 bucks. then clean out all ports, then test the vacuum.