What does the "eco" button actually do? (MY20 ducato)

[activecampers]

Only just remembered I have one!
Van is MY20 160ps 2.3 ducato sportivo.
I was getting 31-32mpg but that dropped over winter to 27-28. Whether that was due to winter or needing a service, no idea. Its been serviced and ECUs updated but not driven far enough to know any mpg change yet

What does the ECO button do? I did press it when I first got the van and it just made it feel sluggish like a 120ps van - so I turned it off

But does it actually do anything except retire 40 horses? Does MPG increase enough to warrant it?

 

[Dramfineday]

Can only speak for my Honda Civic desiel....the eco button controlled certain air con and cruise settings. With eco on, cruise control took longer to get back up to the "set" speed if, for example, I started up an incline.