My 2006 Malibu makes a strange sound on startup but then improves after a minute or so. Anyone recognize this sound and likely cause? I have uploaded audio file.

sorry..hopefully attachment works

The sound was recorded from the ground near the driver'* door. The flex pipe has been replaced recently but I can't find a leak at the joint.

Kind of hard to tell. Sounds like the recording device gets taken away from the sound after about eight seconds. If I had to guess, it might be an exhaust leak.

Could you get us a recording just like this one, but leave it recording until after the bad sound goes away?

This is a longer recording..hopefully provides a bit longer sample

Still can't tell. What does the strange sound sound like?

sounds like exhaust leak or metal vibrating during first minute or 2 after starting in cooler weather...But I don't know much about cars.. The sound is rather loud and my family has also noticed it so it is not subtle but more noticeable. I will have my friend listen as he knows a bit more about cars.

Record like this. Start and idle for 5 seconds. Go to WOT for a moment and back to idle for a few seconds. Take engine to 2500 rpm for 5 seconds. Turn off. Let'* hear what it'* doing.

What is WOT ?

W ide
O pen
T hrottle

He wants you to rev it up one time for that part.