I havea 2003 Dodge ram 1500 4x4......the check engine light is on..... I had it scanned and it said oxygen sensor bank 1 running lean.

My truck has a little miss to it now and my gas millage has dropped from 21 to 11.9....

Where is the other 2 sensors ...1 in front of converter, and one behind it, but where are the other ones ??
Anyone else have this problem?

 

There are only 2 o2 sensors on 03's.

wow if youwere getting 21mpg then I think I might have a problem myself......[>:]

 

It was doing really well on gas... i drove it 360 miles on one tank of fuel...and some of that was interstate driving at 85 mph.........and then some highway, but ever since this sensor went out its been all to hell!

 

i got this code too and the truck ran like crap. found out the connection was loose for the downstream sensor. i unplugged it cleaned out the terminals and plugged it back in. solved. but since you are reporting a miss there might be something else going on too.