98 Escort knocking, no power

I have a 98 ford escort se. I have 2 problems first and most important it just lost all power yesterday, this happend gradualy I could tell it was wasn't running right, but they yesterday on the highway I had it to the floor just keep up with traffic. Then in traffic in town I had to drop it in low and shift up or it would take forever to even get to 30. It has no power or just enough to move and drive, if I floor it. The other problem is it sounds like it is knocking but it's not constant and it seems to do it more when ideling or decelerating, so far I have put plugs wires, fuel filter, air filter. I think it is possibly one of three things, cat converter pluged? Know and easy way to check? (Would it knock?). Timing jumped, would explain knockin. Plus the car has 105,000 miles on it. Or maybe main bearings but no oil leaking(and would not explain power lose). Have no idea? Thanks again! -Josh