Thanks for your input, you know your stuff it seems, whistling is not too loud to be frank but was just a tad worried as usually in the past when coasting down hills mountains always had windows up, so could not hear much, ok thanks again, car is going strong, apart from the mystery coolant loss every 1000miles about half a teacup of coolant, and my chopstick are cluttering and need sorting....keep in touch, diesel owners are few and far between...