99 F150 4.2 V6 Manual

I don't drive the truck long distances, maybe 40 miles a week, but for the last month I have been doing two 180 miles trips on the weekend, not sure if this has a thing to do with the problem, just throwing it out there.

The truck seems a little sluggish, and a little bit rough at idle.

P0133
slow response (heated oxygen sensor bank 1 sensor 1)

P0171
Fuel trim Bank 1 condition

The guy at auto zone said its the O2 sensor on the exhaust manifold, looked up the part but didn't have one in stock.

Ok so today I stopped at my local auto parts store to pick up one, but they told me there are two which I did confirm.

Which side is it?
Is that the problem?
Could it be an air leak?
Can I test them or visually inspect them to figure it out?

I am in no rush, I have all weekend and the parts store is a block from me.

Thanks for the Help
Brian

 

i believe bank 1 is the side where the number 1 cylinder is one that i think is the left side(driver side)

 

Bank 1 is the RH side of the engine as viewed from the drivers seat, just as if you were talking about the RH turn signal. The 02 sensor uses the same terminology.

An air leak can cause the P0171, what effect it will have on the 02, I don't know. Perhaps the 02 sensor has caused the lean condition on the bank 1.

Other will have to chime in for further help.