Name that noise !
 

Hey everyone,

It’s a sunny, yet cold day, so I decided to start my car and remove the cover for a little bit. I noticed a noise coming from the cabin that didn’t sound familiar. Video is below. It goes away temporarily if I rev the motor. Funny thing is, I can’t distinguish the noise under the hood. Is this normal? Am I going crazy?

Not normal, but can't tell what it is. I've listened to it with a high-end pair of Allen & Heath head phones.

sounds like the start of a loose secondary catalysts with the pulses. give the cat a tap with a rubber mallet, or when it starts, put a metal rod on the cat and listen for that sound.

My go-to tool for finding sounds is a metal rod made of copper plugged into stethoscopes, and probing around.

Thanks - I'll try this out this weekend.

Update: Yesterday I checked my oil (all good), started my car and let it warm down to idle. The noise was still there. I tried a long pole and braced it against my CAT to see if there was vibration (nothing) and then drove it around town this time. After driving for a bit and parking it, the noise was no longer there. Do you think this had something to do with the car sitting for a few weeks in the cold?