DPF or Fuel Filter Problem?

[RRTT]

Greetings.

My 2009 2.2 tdci Mondeo has gone into limp mode, no power, no turbo... nothing.

Had an error telling me my DIAFPS had failed, changed that but then the error message just read "DPF Value Not Found" before cutting out a day later, notably only when going round a bend or uphill though.

I'm concerned this is a full DPF failure, but a mechanic friend of mine suggested the fuel filter might be causing the issue and the error message is a confused result.

I'd like to test all the cheap options before submitting the car for a DPF clean/replacement... I'd welcome any ideas.

Thanks

James