ODB II Code 174 only

[exp97]

On my 1997 Explorer XLT, the only code I am able to read is:
0174 System Too Lean (Bank 2). I've seen many postings that include 0174 but they usually seem to state both 0171 and 0174 System Too Lean for Banks 1 and 2.
With only one bank showing this error is it a safe bet that the issue is with the oxygen sensor related to bank 2?
If this is an incorrect assumption, then I would appreciate hearing what other possible causes would only produce this one code, and in what order it makes sense for a do-it-yourselfer to tackle them based on cost and also ease of task. Thanks for any advice anyone can offer!!

 

[cjones101812]

bank 2 is driver's side.

with the scanner connected watch the O2 PID. does the voltage change while snapping the throttle??

check for vacuum leaks, exhaust leaks on that side of engine. check fuel injector pulse and flow in that side of engine.