Was it starting right away (less than a second) before this happened? I don't know what the "pop" would be. Was the engine running fine before? What prompted you to change the plugs and wires? Based on what you've replaced, it looks like it was having starting problems before. What were the symptoms then?
The three basic things you need to start the engine are fuel, ignition, and compression. The ignition is typically the easiest to check first. You've replaced the plugs and wires recently. Make sure that the connectors are seated on the plugs. At any auto parts store you can pickup a spark plug wire tester for under $10. This will tell you if you're getting spark.
Have you taken a look at your distributor cap recently? It's fairly easy to remove. Pop the suppressor cover off and there are three 5mm hex screws that need to be removed. One of them you can't see underneath the cap. I used a universal joint attachment with a 5mm hex bit socket to remove it. It's kind of a tight fit with the fan blade in the way. Also make sure the rotor isn't scorched or damaged. Not knowing much else about what kind of shape your engine is in, the cap and rotor would be the first thing that I would suspect.
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