Read a few threads here on FR2 Engine suddenly cutting out for a split second and then continuing to run. I had this fault with no codes showing along with what felt like enhanced engine braking when you lifted of the accelerator. Never had engine go into limp mode.
Replaced the crank shaft sensor (Febi part) and all is well. Fault seems to have disappeared completely. 2007 2.2 GS Td4
128,000 miles and counting