i have installed a set of denso iridium iw24 plugs in my bmw 635 turbo('87 cartech turbo system).the problem is upon cold starting a plugs tend to gas foul ,sometimes they start to fire after a few min. or i have to remove and clean.i think i've gone with to cool of a plug.also i have a hot msd ign. spark.any thoughts on my problem would be appresiated. thanks kevin