Hi had this one in yesterday and read the codes then cleared them.
P0174 & P0171. Both relate to engine running lean.
All pointers were relating to low fuel but i eventually found breather to inlet manifold pipe had collapsed and split.
The symptoms were irratic idle and both times the eml had been triggered when stopped at lights on a hill.
The LTFT was 19.5
Fuel pressure between 370 and 380 kpa
I have put this post in as there seemed to be very little info on the causes for these codes in this forum.
Hope this helps someone regards Brad
