2003 X-Type 2

2003 x-type 2.5 is difficult to start in moderate cold - cold weather. Must press accelerator to get enough fuell into system to sustain idle. Once this done the engine will idle with minor dips in the tach. Pressing the brake and releasing seems to increase preceived idle on the tach. Also get code p0171 an p0174. Already have replaced, plugs, gaskets, breather hose, imt - orings, checked and cleaned MAF and throttle body, replaced fuel filter, and used injector cleaner. Once engine heats up to normal temp or sits for no more than 5 hrs. Startup is normal but still get occassional p0171 and p0174. Any ideas?