Originally Posted by jrs14855
The most likely possibility is that one spark plug wire is not properly inserted into the distributor cap OR that the contact spring on the end of the wire was damaged. Pull off the cover that holds the plug wires and take a look.
I disagree with cross firing, most likely that would involve two cylinders and a lot of shaking/backfiring, as well as low EGT on two cylinders when the other ignition is switched off.
I respectfully disagree. And so does the science/laws of physics.
If a plug was not connected properly the EGT on that cylinder will be much higher not lower. The CHT on that same cylinder will be lower and not much higher.
The OP has the exact opposite symptoms that you are talking about.
I have the data and the details including busted pieces of more than a couple of preignition events caused by things such as a cross firing.
Now it is possible there is something else going on......but this is too serious to not fully disprove it first.