92 Mustang bucks and shutters when accelerating

92 Mustang 2.3L standard........When accelerating the car starts bucking and shuttering in 3rd and 4th gear.....I have replaced the fuel filter and the catalytic converter.......the catalytic converter was full of carbon and was completely stopped up.......the car still has lots of power as u can do 75 in 3rd gear but it really shutters getting there........it almost feels like it isnt getting fuel or a spark plug is fouling out........the car idles really smooth and i cant hear a miss in the engine........sometimes the problem is really short lived and it only gives u one or two shutters and then sometimes it keeps shuttering until u level off on the accelerator......im leaning toward a sensor going bad......but im not sure......im thinking maybe this problem might be linked to what knocked out the catalytic converter..........Please any suggestions or help would be appreciated.......thank you..... I also noticed the Tach aint working ........could all of this be related.......

eb33@cleaninter.net
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