Speedo not working offside wheel not turning when in gear
2005 Citroen Berlingo 1.9 diesel

Speedo is driven from the differential,
but I'm thinking when you changed the engine one driveshaft was disturbed.
most likely the inner C/V joint isn't fully in,
done it myself before,
red face!
~Big hammer and lump of wood and,so as not to feck the inner c/v boot,carefully drive the inner c/v fully home into the diff.
Really doesn't take much for them to spring out of engagement.