have just noticed that i am getting a creamy mayonnaise type gunge on my oil filler cap,thought the worst andsuspected a head gasket failure or the like checked everything and all seems ok no coolant loss whatsoever,the only thing i can think of is i have just started a new job much closer to home (2miles) and perhaps the engine is not warming enough to get rid of any condensation that combined with the falling temperature what do you think guys im a little puzzled. ps i use a fully synthetic oil from putoline