× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network
Re: 2004 F150 5.4 '5' Lean codes P0171 and P0174
Posted to Technical Discussion Forum on 2/15/2007

That freeze frame also looks like it was during a warm up [...] he has a vacuum leak that is more noticeable during the warm up cycle that lessens after component [...] did a 1999 Maxima that could be leak checked warm with every method I know of but was found... Login to read more.