system running lean question

[croadmar]

Hey I got a code P071 - system too lean in bank 1 and 2.

I changed out all my 02 sensors about a year and a half ago but, I bought my 03' V6 4.0 ltr in Washington and now live in Colorado. Would the Elevation change ( i live at 5,200 ft) effect anything making my truck start running lean or should I check the O2 sensors and maybe the MAF sensors? I don't see how the sensors would go bad in a year and a half.

Any feedback is appreciated

 

[bobbywalter]

less air is a potential issue, but i would guess you need to clean the maf properly.

in this code what is happening generally is the engine computer is running the fuel trim at its limit to the rich side but still coming up short according to the o2's. if the maf is reporting correctly its usually a vac leak on the # 1 bank or some clogged or dying injectors. so cleaning the fuel system properly and making sure the filter/pump is flowing good via a volume test may be in order if the easier stuff proves to be in order.

if your lucky its simply a matter of cleaning the maf.