2001 Passat Rattles On Start up

I have a 2001.5 volkswagen passat, with a 1.8t engine, it has 63,000 miles. A few months ago my car started making a very loud rattleing noise whenever I start it. It lasts for about 3-4 seconds and then it goes away. While getting my oil changed, the guy at midas said that it was definately an internal problem with the engine. And that it might have something to do with the oil pressure. Or something along those lines (he was kind of hard to understand).


Any ideas you guys have would be a HUGE help.