Had plugs,wires, cap, rotor, and coil replaced.I made sure firing order was correct and is still running rough.I also changed the fuel filter and treated tanks for contamination.
My car has a manual transmission.
Hey there, the first thing to check are any trouble codes, even though this is pre-OBD II (Ford MCU or EEC-Iv engine management systems), there are inexpensive code readers for these engines, or your local parts store can read the codes. This should help determine if the problem is ignition misfire (distributor pick-up, ignition module possibly), or fuel (low fuel pressure, dirty injectors, dirty/clogged idle air control valve, dirty throttle body possibly). Leaks in the air intake can also get you - loose or split hoses, EGR valve not closing completely.
I would recommend having a rough idle inspection completed by a mobile, professional mechanic, such as one from YourMechanic, to diagnose this problem, get an accurate assessment of damage and cost estimate for repairs.
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