Blinking Check Engine Light
 

I have a 2001, 4 cyl- 2.0 liter engine where the check engine light came on blinking. The engine runs rough as though it is mis-firing. It is not producing any engine codes. I replaced the spark plug wires yesterday. The plugs, platinum and rated for 100,000 miles, have approximately 30,000 miles on them and are clean. Does anybody have any suggestions as to what the cause may be? Thanks.

Blinking Check Engine Light
 

An update: I brought it to my mechanic and it turned out the 4th plug was not firing. The coil pack was n/g.