Hi all,I have a 2001 Explorer Sport with a 6cyl/4.0L engine in it, i have been told it is what is called 2nd generation engine, because it replaced the original engine that was in these models. Anyways, my check engine light came on and i have recieved these codes, P0401, P0171, P0174. Any ideas on where and what i should be looking at to help solve them. Any and all help is greatly appreciated. Thank you in advance.