Hello everyone, I have a 2006 Audi A3 completely stock and have run into some problems after my drive accross country.

I currently have these fault codes
P0507- Powertrain, RPM higher than expected
P0300- Powertrain, Random/Multiple Cylinder missfire
P0304- Powertrain, Cylinder 4 misfire
P0171- Powertrain, System too lean (bank 1)

and these next codes are pending..
P0302- Powertrain, Cylinder 2 misfire
P0303- Powertrain, Cylinder 3 misfire


Can anyone tell me what this means in terms of repair? If so how much it would cost in parts? If any other information is needed just ask and I will do my best to get it.

If it helps, I used the android app "torque" and the "pxi kiwi" OBD2 bluetooth adapter to get these codes off my ECU.

Thanks!