bigdaddyhoke

alright, so i have a 1992 ford mustang lx with a stock 4 cylinder in it. it wont get above 5 miles an hour, and the middle two cylinders arent firing. now, just fyi, i am pretty car illiterate, but i do have some more knowledgeable friends helping with it. i have replaced all the spark plugs, and still nothing. the car smells of gas when it is cranked. i hooked up my code reader today, and i got 998, 218. which is saying that the IDM is bad. does anyone have any opinions on this, or what i should do, besides replace it? do the cylinders not firing have anything to do with the IDM, or are they completely seperate problems? also, idk if this wouldhelp or not, but around the time this happened, my ac also went out.