What does the trouble code of P0174 on a 1997 Mercury Courgar XR7 with a V6 engine and how do you fix it?

Answer 1

Look for a vacuum leak,and clean the MAF sensor: I had a vacuum leak at the throttle body, which was part of an assembly Ford dealer sells. They dont sell just the rubber elbow I needed, so I optioned to get the assembly and replace the PVC while I had it apart. The vacuum leak at the throttle body was giving me DTC P0171 and P0174, rough idle and surging. After I had gone through cleaning the MAF sensor and cleaning the combustion chamber, throttle body, and fuel injectors with a professional fuel system cleaning kit from Berryman Chemtool. I found the vacuum leak. I have replace the vent tube and PVC valve. I reset my computer and I don't have any codes.