2009 Montero Sport error code P0093

I have a Montero Sport 2009 model and the car stalls at low speed or idle
then check engine light comes on at. After a time it then goes out but it will
return later.

I have had it scanned and they said it came up with Fuel Leak Problem, so
they checked all the fuel lines and could find no leak, so they changed the
fuel filter during our first visit. That seemed to fix it then a few days later it
stopped again and the check engine light came back on.

The second visit they dropped the fuel tank and cleaned out the lines and
fuel tank. Everything seemed fine until later that day it stopped again and
the check engine light came on. When this happens the car seems be down
on power and surges when driving.

Any help would be great.