i have a 94 wrx it hesitates when cold or hot at times more when just started and really backfires when changing gears or realising throttle in 2nd or 3rd gear down hill and letting in hold itself back when holding back the engine real drags the speed down quickly as if it cant breath any ideas also idle does drop at times and most times it sits just above 1000rpm can i get a coil pack coversion or where is cheapest place to get coils if they are the problem?

 

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