What cause flicker noise in the engine area after replacing spark plugs valve gasket and wires for 99 Chrysler Sebring Convertible?

Assuming that the noise started after the repairs check to be sure the plug wires are connected properly ( pushed on all the way ) and are not touching each other or close to metal. That spark will find ground one way or another, if the plug or distributor connection is bad it will jump across wires or to the engine to reach ground and will make a snap sound, if its not really obvious then look at your engine in total darkness if you can see little lightning bolts jumping off the wires then you will know which one has a problem.