Engine Performance problem
1981 Chevy Citation 6 cyl Front Wheel Drive Automatic 130000 miles
im at a lost, can anyone help me. My car idles great, compressiion is good in all cyl. Spark wires, plugs, rotor, and cap all been replaced in the last 10miles. It is missing the exhaust from the cat back tho. But what I was wondering is at speeds over 45mph it feels as tho the engine is missing because it is kinda jerky and if you push the peddle to the floor under 45 it tends to want to die, but at idle it runs awsome, I dunno what it could be. My guess is vaccume lines does this right?