2003 Windstar> The check engine light went on, I replaced the two O2 senors, codes came back
I replaced the two O2 senors, codes 171 and 174 and the EGR valve.. I drove it 85 miles
and it still read not ready for inspection. I drove it another 25 miles as per the mechanic
and the light came back on with the same codes. What does this mean?