chef_for_life

i have a 2001 screw 5.4 ltr 4x4 it threw a code a couple of days ago. I took it to the not so brilliant guys at autozone to get a free code read. it was saying lean on bank one and bank two. from my experiance before that could be either o2 sensor or mass air flow. but i am new to ford so im not sure. but back to the rough idle it started fine today ran around for a while then when i pulled up to a stop light it was idling rough could the mass air flow sensor cause that ? or what elso could be the cause?? thanks in advance

Speedy Mike

do a search buddy, that could be one of a billion different things.. first id clean the maf with non residue electronics cleaner, check for vacuum leaks, check fuel pressure, could be the DPFE for the egr, could be dirty egr ports in the intake, or a dirty egr, could be fuel pressure regulator, could be the iac, could be the tps, could be anything, from my experience..

seniorFORDtech

a common concern for this is the pcv tube rubber fittings get soft over time and get sucked in causing a lean condition...
follow your pcv valve on the right valve cover there is a solid plastic tube at the ends there are rubber fittings check all those fittings for vacuum leaks (holes) ford sells a complete hose assy with the pcv valve...

mulehauler

I had the same problem a coulple of months ago it was an vacum line behind the throttle body that had just gotten old

Dsav

i got the same thing goin now, how many lines are there to check?

Speedy Mike

lol, just have to look, theres a bunch..