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My engine started loping again.
I pulled the spark plug wires 1-by-1 to see If I'm getting spark. Each plug dropped the idle rpm except #4 acted opposite of what I expected. When I pulled the wire to #4 , engine idle increased. What is that a symptom of?

Check the plug wires of what ever 2wo cylinders that fire BEFORE number 4 and after $4. Make sure that those plug wires are not touching the #4 plug wire. NO, i don't care if u have brand new plug wires, old ones or any other kind.

Plug wires of consecutively fireing cylinders must NOT touch each other. THis is true of ANY gasoline engine with more than six cylinders or if ground strap wires are connected to each wire or if the wires must cross each other then cross them at right angle in tewo different places..

Edit: What u have described is especialy the case of where the plug wire that fires BEFORE #4 is touching the #4 wire.