misfire at 5500 - 6000 rpm

[blackace]

Hello,
I'm getting a misfire from my 172 when the car hits say 5500-6000

Has anyone had this before and how did you solve it.

i think it might be the ht leads

 

[DARKO]

Coilpack? £40 from GSF. The leads are meant to be pretty bullet proof.

 

[S22 JGS]

waterin sparkplugs