I have a 2001 Ram 1500 with a 5.2L engine. I am getting a code saying I am lean on bank 1. Could you tell me which one is bank 1 and would this be from a faulty 02 sensor?

 

unless you have a California emissions, our trucks only have one front and one rear sensor. so bank 1, sensor 1 is the front.

it might be a bad 02 sensor, but its more likely that you have a vacuum leak in your intake, causing it to actually run lean. the most common problem that affects 100% of these engines is the leaking plenum. do a seach on here for about 1 million posts on this problem. other associated symptoms are spark knock under load and low power. don't ignore this, the lean condition will cause higher temps and either blown head gasket or cracked head.