checking the harness and coils tomorrow, the harness is looking a bit ratty with a couple of exposed wires that i can see. wire at the fitting on the earth lead is looking a bit corroded. will rectify these tomorrow. cooler is fairly new so i don't think that is the problem. coils look in reasonable condition, can see any cracks in the boots or on the coil itself, doesn't mean that they are good though. picking up a set of proven coil packs on Monday to try out