So I've been reading on here that Audis are supposed to be warmed up with moderate driving and not idling. What is the difference between Audis and cars that 'should' be warmed up? Someone said it can ruin your cat, if thats true wouldn't it ruin the cat on any car? And if you're not supposed to idle to warm up wouldn't it also be bad to idle to cool down the turbo?

 

When you start up an engine in cold weather it's bad because oil isn't where it should be to lubricate parts. The oil is thicker during cold weather making it rough on the engine. Just sitting there idling the engine isn't the most efficient way to warm up your engine, and it causes more pollution. Low RPM's and easy driving is though.