Failed Smog Test

[malamorian]

I have a 99 explorer V6 OHV.
Took it to have it smog check and it failed.
It passed all the test except OBD system check it has the PO171 system too lean (bank1) and PO174 system too lean (bank 2)
Now my check engine light was on will that make it automatically fail?

Check your mass air flow sensor readings,you might need to replace it.

 

[wagonmaster69]

Cleared the codes driving it allot and light still off.
Now going to get it tested today.
Now on my receipt say they will retest it for free if they do the work.
If they try to charge me again I'll just go to another shop.

 

[wagonmaster69]

It passed yea.