Cam swap is complete(buddie+me). We did a small up- grade to a 218/224 cam from stock. We did a great job with no problems and in less than a weekend. .Now getting po300 but car runs good. Plugs + wires are brand new thanks to a local parts store. All wires were arching at plug boot after a few hpurs of start up. I believe the distributer is original 92,600 miles. This opti was reinstalled. No light shows going on now. Anyone had the same thing happen, or close? I'm wanting to fix what's causing it. Ole school had no codes. Rick Z

 

Its possibility that the irregularity of the crankshft motion, caused by the overlap in the cam, at low RPM will be enough to fool the PCM into interpreting the signal from the crank position sensor as a "misfire". But with a cam as small as that, it shouldn't be a problem. Might want to check more carefully for misadjusted valves, burnt wires, etc.