Have a 94 ford ranger XLT 4.0lL Extended Cab. Having rough idle and occasional stalling. Usually at idol but lately is happening at driving speed also. Used to run perfect. Then one day CEL comes on and it starts running rough and trying to stall like something is clogging the fuel. Then while driving would jerk like it had cleared the fuel line andl light would go out and run perfect again. Couldn't figure what was causing this. Changed Oil, plugs, Fuel filter was changed and injectors cleaned by shop and a new fuel filter. last year but does not have but 5000 miles since installed. As time passed the light staying on became longer and times it ran perfect where shorter. Now Light stays on all the time. Have to drive with 2 feet. Always started without problems. Now I am getting occasional back fire and Black inside tail pipe. Is it possible for the ICA to be the culprit. Could it clog and unclog and clog and unclog till it stays that way or when it clogs once it stays that way. Or perhaps a loose or corroded electrical connector, Clogged exhaust system? PCM was replaced about 6 months before these issues started a year ago. So I don't believe this to be the issue. My OBD1 is broken so I have no codes yet. Need to get a new one on payday. I have no formal automotive training. I have an IQ of 147, Usually very good at figuring out problems and fixing them on almost anything. Computers, laptops, video game consoles, Arcade Game Machines, slot machines, tv's, Furnaces, Home A/C units, Etc. etc. I am self taught in everything. But this is driving me up a wall. Cannot figure what would cause it to run perfect then messed up then perfect. Any one that can help me on this I can help you with advice on fixing some of the above mentioned items. Thanks in advance to anyone that can help.