okay i scan my 01 f150 v6 4.2 i got three codes one was an 02 sensor (p0153 bank 2 sensor 1) the other codes were p0171 System too lean bank 1.! and the other code was p0174 system too lean bank2! k i replaced the 02 sensor and it clear the 2 codes the (p0153) and (p0171) but the p0174 keeps on comin up i wanna replace the other 02 sensor on bank 1 you guys think that would help since it cleared when i replace the 02 sensor on bank2??? any suggestions im takin my emissions test next month i got to clear the code..... !!!!!!!!!!

 

Do a search in the V6 section for intake gaskets leaking.

 

Those codes tell you your O2's are working as they should- perfectly...

You have a vac leak and/or a dirty MAF sensor..

 

okay thanks!!! but im kind of new to these stuff how do i look for a vac leak and where is the maf sensor is there a way i can clean it or do i have to replace it..??

 

idunno , try the V6 section or maybe someone else will chime in that know's..