Cold Start Engine Noise
Just bought my *new* (first owner owned the car for 2 months and less than 150 miles) 2010 Cobalt. It's a base model 2 door Coupe with an auto and I'm very happy with the car so far, however I have noticed that when I start the car from dead cold, there is quite a lot of chattering from the top end of the engine. It soon goes away after 60 seconds or so, but in all my previous cars the only other one to make so much noise from cold was an old Ford Escort (boo hiss) with hydraulic valve lifters.
Is this chattering noise normal?
And for my information, I'm guessing there are just valve shims in there like there are in most modern 16v engines... am I right?