How do you replace the fuel sensor on this car?

Look in the trunk right behind the rear seats under the carpet. Theres a plate on either side that comes up to get to the sensors for each half of the tank.

 

Check the wiring and the connector on top of the tank first. Mice like to get up there and chew on stuff. The terminals in the connector can also corrode and cause poor connection.

Thanks, The local dealer told me he had to remove the fuel tank for $672 plus parts.

in 00, they may have moved the access panel to under the rear seat.

i'm not sure.

but it will be one of the two locations.

My local repairman found both under the back seat and will only charge $150 in labor versus the Subaru dealer for $672.

wait - a "dealer" told you they had to drop the tank??