Hello All

What are the main causes of missfires??

I have not long had the car setup at MSD and its been absolutely fine but in the last week ive had 2 missfires, 1 big one! in 2nd gear at good boost and a slight one last night in 5th using the torque of the car on the motorway to overtake. The one on Saturday i sensed was coming as for some reason the car felt like it had much more power than normal....the temperature was much much cooler than when it was setup...could it be this??? I have replaced both of the coil packs almost 2 years ago (4500 miles) as i was advised to because not knowing if they had been done before. I removed the plugs last weekend (pp8) and cleaned them all up and checked gaps which were fine (0.7mm) only thing ive not replaced is plug leads. But could it be something else ive missed. Ive checked all the boost hoses which are ok and the amal valve connections and pipes are all ok too.

Its so intermittent that i hope its not going to be to difficult to track down the fault.
Hope you may be able to help me

Mart