2002 B2300 running lean
 

I have a 2002 B2300 that is running lean, and wont rev over 3k rpm, I know that its not he fuel pump because the guy I got it from had it replaced then gave it to me cause he didn't want to deal with it, I don't think its mass airflow sensor either cause I cant rev over 3k rpm with plugged in or unplugged, any help?

If mine, first thing I'd do was replace the fuel filter, check fuel delivery (like maybe the fuel sock in the tank is clogged, or tank vent system is preventing fuel flow somewhat).

Why do you think lean??? Did you search Ford Ranger boards for help?

That was just the code it threw, and the B series trucks and the rangers are pretty much the same truck then?

In USA, 1994-on B series trucks are same as Ford Rangers, except for some sheet metal type differences.