2003 pontiac sunfire GT

When they say "bank," they're referring to cylinder banks 1 or 2. Bank 1 is the passenger's side and has cylinders 1-4 on it. Bank 2 is the driver's side and has cylinders 5-8 on it.

P0171/0174 indicates that the long term fuel trims have reached a maximum (should be somewhere around 30-35%). Fuel trims are how much fuel the PCM adds or subtracts. 0171/0174 indicates that the engine is running lean, meaning that outside air is getting past the mass air sensor. The O2 sensors see this excess air and the PCM responds by cranking up fuel trims to add more fuel for that more air.

Possible solutions include:

• In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
• Inspect all vacuum and PCV hoses, replace if necessary
• Check for a dirty fuel filter and proper fuel pressure