1997 Ford Escort ignition problem

I am trying to repair a 97 escort, the problem is that it is only getting spark in 2 cylinders, my first step was to check the wires, wires were fine. Next I replaced the ignition coil, (first logical conclusion based on design), same two clyinders would not fire. Then I connected the scan tool and got a code 0351: Ignition coil A- Primary/secondary circuit malfunction. Checked all wires found no problems, tryed another coil, just in case 1st one was defective-Nothing. So now I'm down to the PCM that I purchased reluctantly due to the price and fact that it cannot be returned. Well that did not do it either. I am at a loss don't know where to go from here. The car does start, but only runs on two cylinders I was thinking possibly the CPS, but wouldn't that throw a code at me? Any help is appreciated. Thanks