1996 Ford Aspire • 165,000 miles

My car ran fine, then one day it just started running VERY poorly, stuttering, failing at hight (3-4000) RPM, and not reaching speeds over 45-50 mph down hill. I have had suggestions from timing, clogged fuel filter, clogged Cat converter to fuel filter. I have done some troubleshooting, replaced the plugs/wires/cap/rotar and fuel filter in engine compartment, with very little improvement. I did loosen the distributor and manually turn it until it ran better at higher RPM's, giving me about a 10% improvment. I am kinda lost at this point. I know I need a mechanic to read the computer and find out exactly what is wrong. But money is a tight issue right now, and I'm seeking the advice from someone that may know what the problem is most likely to be, before I spend hundreds on getting it fixed.

Any help or advice would be very much appreciated. I plan on adjusting the timing tonight.
November 13, 2012.

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