Help PO171 and PO172 Codes

I just went to auto zone to have my cel read, it came back with 2 codes. a po171 and po172. The service person helping me told me it was o2 sensors in the first bank. However when I left the store, my cel light went off. I do experience some rough idle when stopped only in drive, not park, and only when its cold. I have searched around here for answers, and have seen intake manufold gasket, no mention of o2 sensors. What is the general opinion out there? I am stuck with the o2 sensors if I buy them and its not the problem. Thanks all in advance for your replies.
Jim

Your best bet when getting codes read at AutoZone is to go in, get the codes read, write down the codes and leave. Then go here (http://www.troublecodes.net/isuzu/iszuobd2.shtml) to find out what the codes refer to. Wearing earplugs so you don't have to listen to them try to sell you an O2 sensor for every CEL helps too.

P0171 is "Fuel Trim System Lean Bank 1" and P0172 is "Fuel Trim System Rich Bank 1". There's a pretty good chance you may have a bad IMG on the passenger's side (Bank 1) just from your symptoms and the rich/lean codes your ECM is throwing.

Were it a bad O2 sensor you should have had one of the O2 sensor codes (there are almost 30 of them since your vehicle has 4 sensors) set as well.

Thanks for your reply. I saw you noted in another post the opposite of bank one and two as you stated in mine. I am also not sure as to what an IMG is. My vehicle is a 2000 Honda Passport 4wd 3.2l. I just wanted to clarify if bank one is indeed on the drivers side.
Thanks

Thanks for your reply. I saw you noted in another post the opposite of bank one and two as you stated in mine. I am also not sure as to what an IMG is. My vehicle is a 2000 Honda Passport 4wd 3.2l. I just wanted to clarify if bank one is indeed on the drivers side.
Thanks

Oops, my bad. Bank 1 is passenger's side and IMG is me being too lazy to type out intake manifold gasket.