92 jeep wrangler looses power

I took my 92' jeep offroading, and since i got back the engine sounds heavy as it might stall on me, but it stays on, And the other problem its that it looses power going up hill, almost not moving-- even when getting momentum and flooring it.... It actually starts gaining power as i decelerate to a point were i can continue just enough to gain momentum.... Anyone has an idea what it might be????

check cat they clog up if running to rich