Whirring noise when accelerating with a cold engine. Hi all, I have a well maintained 2012 T31 ST, with 65,000 on the clock. I have noticed recently that when the engine has got cold overnight I get a faint whirring noise under acceleration, like you would get from a timing chain. If I ease off on the acceleration it decreases. This persists until the engine is thoroughly warmed up, about 8 or 10 Km/s and it never comes back. I have checked that the oil level is correct and I will mention it to the Nissan Dealer when I take it for it's 70,000 service, but I am curious to know if any other members have had a similar occurrence.