Engine Mechanical problem
2000 GMC Jimmy 4 cyl Four Wheel Drive Automatic 96000 miles

My engine light comes on and then goes of with in hours or maybe the next day. I ran a dignostic test and it came back with the codes of p0101 p0174 p0171. What does that mean and I just had the fuel pump replaced last week. I have put so much money into this SUV than any other car I have owned. Its Killing me.

P0101 - Mass air flow sensor circuit range problem.
P0171 - System too lean Bank 1
P0174 - System too lean Bank 2

Check the Mass Air flow sensor connection and test the sensor as well. You can look at the data live if your scan tool allows it.
A bad MAF can cause all three codes.