2002 Ford Ranger Will not complete all readiness tests

What do u have for codes ??
check fuses
I do not suspect PCM it should be protected by fuses
check and suspect the wires
check for vacuum leaks check MAF sensor

The codes I am getting are P1131 (Lack of HO2S11 Switches- Sensor indicates lean) on a regular scan and P1000 (OBD Systems Readiness Test Not Complete) on a continuous scan. I have a Blue Point (Snap-On) YA3120 CanOBD 2 & 1 diagnostic scan tool. I am no longer getting the P1132 (rich bank 1, sensor 1). Flashing emblems on scanner said CAT and EVA (I'm assuming for evap system) were problems with the readiness tests. Now all I am getting is the EVA. The only thing remaining constant is the lean code. I am suspecting a bad injector, but the readiness test part is throwing me for a loop. Any suggestions would help.
Thanks

Possible causes are :
· FUEL SYSTEM
Excessive fuel pressure , check for leaking or bad injector ,leaking fuel pressure regulator,low fuel pressure ,engine low on fuel , vapor recovery system fault.

· INTAKE SYSTEM
leaking air after NAF sensor ,intake gasket ,vacuum leaks ,PCV valve
· EGR system
check EGR valve if stuck or leaking check for exhaust leak before or near the O2 sensor ,check oil ,check cam timing





do u have any symptom :lack of power ,spark knock ,buck ,jerk ,hesitation on acceleration
if so suspect MAF sensor