1999 SAAB 9-3 repair Question No acceleration, lacks any pow

We have a 99 9-3 saab that appears to have lost all ability to accelerate. You can punch it and it barely gets going. And can't go up any hills faster than 40 mph. We ught it used and it has always had a bit of a delay, can't say I ever felt any turbo kick in. But in the last 3-4 months it has ealy died out. Actually afraid to pull out in traffic. We pu in a new catalytic converter, since we were told that was plugged- nothing. I put in plugs and air filter. Just hoping it might be simple. It seems to run very smoothly, starts fine, no rough sound or backfires, just no power when you try to accelerate. Any ideas I can try?