Hyundai Repair: 02 sonata check engine light, intake plenum, frequent problems

Question
my check engine light has been coming on. I had it run through a computer and it came up code 303. they said it had a misfire in cylinder #3? what do i need to replace? spark plug?ignition coil? not sure...thanks

Answer
The number of possibilities is large, but the most frequent problems with misfires are with the items you mention and the plug wires.  If you've got a four cylinder, these items are fairly easy to check.  If you've got a V6, the plug and wire are going to be buried under the intake plenum.