Lean Codes! Help!

[greenmachine05]

Ok so this is my first forum. And I'm having problems with my 05 gt. It's been in and out of shops for about 2 months now. Throwing codes that it's running lean in bank 1, and bank 2. Codes P0171 and P0174 to be exact. I don't know what else to do because no one can seem to figure it out. Help. Please.

 

[SpartaPerformance]

What have they done so far?

Possible causes:
• The MAF (Mass Air Flow) Sensor is dirty or faulty Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
• There could be a vacuum leak downstream of the MAF sensor
• Possible cracked vacuum or PCV line/connection Faulty or stuck open PCV valve
• Failed or faulty oxygen sensor (bank 1, sensor 1)
• Sticking/plugged or failed fuel injector
• Low fuel pressure (possible plugged/dirty fuel filter!)
• Exhaust leak between engine and first oxygen sensor