My brother asked me if I could help him with his ranger that is having problems. What he explained to me was, in the cold, when idling the truck will rock back and forth and then die. The codes we have on the truck right now are P0171 and P0174.

I don't know much about this kind of thing, any help would be great. Is it something that needs to be fixed fast or can I put it off to summer, I have to go back to school in Oregon so I can't come back to California, so if it is something that needs to be done fast, is it expensive?

Thank you

oh and it is a 1997 Ford Ranger 4.0L 2WD ex cap

 

Cyl banks 1 & 2 too lean, suggests a vacuum leak. So think about a vacuum leak that could affect both cyl banks. Rubber vacuum lines, stuck open PCV valve, dryrotted rubber line to it, leaking intake manafold gaskets, are some things that come to mind.