I have a 2000 Tiburon with just below 90k miles and I am having some trouble figuring out a ignition/ Fuel problem I have. A couple weeks ago i was getting a bad misfire in cylinder 4 to the point where I just got about a half mile from my home when it started and had to turn back. I Ran a Code check and had the Cyl. 4 Misfire code. Cleared it and started replacing stuff. so far. Plugs and a Coil have gone into it and it still is misfiring but not so bad as to throw a code but its still worrying me. Also its been running very bad and the misfires are getting more frequent the longer its taking me to figure out what it is. I am about to change the spark plug wires soon, I didn't before because they only had about 2k miles on them because I bought the wrong spark plugs when I bought the wires and went ahead and installed the wires and left the old plugs. please let me know what else I should check and how to check it before I have to shell out a grand for a certified Mechanic to tell me whats all wrong with it.

Recap:
Problem: Persistent Misfire
Engine Code : Cyl. 4 Misfire
Actions Taken:
Spark Plugs - changed -Pre-gapped NGK Plugs
Wires - less than 2k miles on them about to change
Ignition Coil - Changed.

 

Spritz the intake manifold gasket along the seam where manifold meets cyl head while idling,,, see if it changes when spray hits vacuum leak (if it has a leak)

 

thanks i pulled the ignition wires and two out of four h\where broken off on the spark plugs so that fixed it. runs like a champ again.