How many miles on tune up end?
Good Ac Delco plugs and filters?
What is fuel pressure reading?
Code101 is MAF sensor is not reading what the computer has figured out for the reading.
In other words the VCM is not happie with the MAF sensor reading.
Code 174 is fuel trim is lean on bank 2.
First thing I would do is confirm proper fuel pressure 60/66 lbs specs.
Also clean MAF air flow sensor with MAF sensor cleaner.
Make sure air filter and air intake hoses are good shape and no air leaks on them.
Do you have a K&N ait filter or cold air intake setup?
To repair for the codes you have you will need a good engine capable scanner and some good repair info.
Get the code repair flow charts for the codes and go threw them.
Replair flow charts are in a factory repair manual or a All Dat online sub,
http://www.alldata.com/products/diy/index.html
Let us know how it goes.