Laguna misfire?

Hi, i have a Renault Laguna 1996 1.8 petrol engine that has a intermittent misfire all through the driving range some times it can go for days without a problem and other times it will drive you crazy my engine has a static distributorless ignition i have tested both ignition coils one of them gives me different reedings on the primary side when the car is misfiring i get 25 ohms and when the car is working properly i get 1 ohms does this mean the coil has an intermitent fault.