2000 Subaru Outback, needing help finding what's wrong. Bogs down when in gear.

What is your question?

Start's and Idols fine once warmed up. Bog's down/no power when you put it into gear and push on gas. Changed the map sensor but the only change was the check engine light went out but did not fix the problem. If someone could give me an idea before I take it in and them tell me that I need to change everything..

What makes this problem better or worse?

Pushing on gas makes it worse.

How long has your 2000 Subaru Outback had this problem?

1 year and then it just sat in driveway.