OBD II error code 0174

Getting this error code 0174 how do I repair this problem, 2004 Endeaver 55k miles.

Hey There GC! I was able to find the code for you! "System too lean (Bank 2). Basically this means that an oxygen sensor in bank 2 detected a lean condition. (Too much oxygen in the exhaust.) Bank 2 is generally the side that does not have cylinder 1. Could be a bad O2 sensor. Could be a dirty MAF sensor, and can also be a vaccum leak downstream from the MAF. Hope this helps