What is the location of the FUEL AIR RATIO SENSOR on a Subaru Outback, 2001,. 2.2 L ?

Sounds as if your fuel pressure regulator has gone bad. You didn't say what codes the O2 sensors tripped. I would change the regulator before chasing down the sensor code. I hope this helps. Take care.

Po340 is a cam shaft sensor and po462 is low voltage on your fuel guage. So i assume you are haveing fuel level issues. If you can turn wrenches you can do these repairs yourself. Just do a google search and you can get some youtube videos of sensor replacement and location. Have fun.

there are two ways your car controls its idle
the throttle position sensor and the idle air control.
if the idle is rough or wanders get the idle air control checked and cleaned up. its the most common poor idle fix

http://www.subaruoutback.org/forums/66-problems-maintenance/28047-98-obl-where-exactly-fuel-pump-relay.html

The definition of Diagnostic Test Code (DTC) P1133 = "FRONT OXYGEN (A/F) SENSOR HEATER CIRCUIT HIGH INPUT"

Please note that DTCs (A.K.A. "fault codes") NEVER tell you what parts to replace.
The DTC here is telling you which CIRCUIT is malfunctioning. The circuit must be diagnosed to find the exact CAUSE of the malfunction.

The possible causes of this DTC are:
> Battery short circuit in harness between Engine Control Module (ECM) and front oxygen (A/F) sensor connector
> Faulty ECM

Please also note that this is NOT a typical O2 Sensor circuit. This is a 6-pin Air/Fuel Ratio sensor. Proper scan tool and datalink interface equipment is REQUIRED to properly diagnose these circuits.

Where the parts are located:
The A/F sensor is located in the exhaust pipe in front of the catalytic converter. The ECM is located Under the carpet in the passenger front foot-well area. The circuits are located between the two.

Please also Review this article:
What Else Could Be Wrong?

most fuel pump relays are located in the main fuse box,under the hood. look for a black box on the drivers side,or passenger side fenderwell under the hood. lift cover off and look on underside of the fuse box lid for location of the fuel pump relay and main engine fuse.hope this helps and thank you for choosing fixya.com

all 5spd from legacy legacy gt outback will fit from 96-2002 they have same gear ratio you will have to change over mounts and speed sensor

The fuel pump relay is located beneath the vehcle's rear close to the fuel tank. See image attached.

P0170 Fuel Trim Malfunction (Bank 1), could be fuel filter, mass air sensor, or low fuel pressure.

technically it is a 2002 (first year or outback) it is in the engine compartment next to the brake master cylinder