I have a 1986 Subaru GL-10 in great condition (2nd engine and only 189000 miles). But recently, this car has had some sort of really weird acceleration problems. For starters, when going up ANY incline, the car starts making a 'pounding' noise and decelerates. I have to then let up on the gas and EASE into it... Very slowly. I have been successful in putting it into 1st, then 2nd, and eventually into DRIVE, but I don't feel that it's a good way to drive an automatic. Also, if I try to force it into a higher gear (flooring the gas), it'll go up into the next gear, but will sputter greatly, and sometimes die. And, while all of this is happening, the engine will sound very rough. Once I am on level ground and up to speed, the engine sounds smooth again. I'm not quite sure what the problem could be, but it's coming from where the engine meets the transmission, as it sounds to me. This is a good car, and I would like a few more years out of her. Please help if you can. Thanks in advance.
Mileage: 189000 (2nd engine)
Engine Size: Not sure (I think it might be 1.8L, MIGHT be wrong though)