Unexpected Rattle Noise?
 

So my car sat for about 2-3 weeks because I needed to get my clutch disk replaced and just didn't have time for it. I also didn't end up turning it on at all, no one did anything to it.

Now all of a sudden there's this rattling noise that was heard since the first time I turned the keys after the replaced clutch. It only happens in lower RPM's, and it starts about 1-2 second after the engine turns on and remains constant. I tried filming to the best of my ability.

My only guess is either EGR valve (as it seems that it's the one vibrating most?), if not my mechanic says maybe a fuel injector? Can't be the alternator... and I sure hope it's not one of my apex seals going bad. Although based on what I could find on the forum, if the rattle gets worse in the high RPM range, then it's a clear sign of seals.... Could it also be a valve other than EGR? SSV only kicks in above 5k though... I know my air pump mounts are broken, but I tried moving it and it didn't settle the noise. Car seems fine, no power loss issues... It does feel a little jolty, maybe I'm not used to the ceramic disk gripping so well. Had an organic before. I also thought it might be my air pump since my mounts for it are broken, but tried moving it by hand and didn't help.

Here's a link to the video:


Any thoughts greatly appreciated. Thanks in advance!

This will sound silly, but take a stick of wood, hold one end to your ear and the other to various engine parts. When you land on the one that's responsible for the rattle, you will hear it much louder in the stick. This way you can narrow down what is rattling.

I'll do that soon (hopefully). I know my mechanic has (or at least HAD) one of those mechanic stethoscope thingies. I'll ask him if he still has it tomorrow. Funny thing is, I heard the noise this morning (it was like 10 degrees Celsius), and at around 5PM when I drove again after the car sat in the sun and the weather hit around 20 degrees celsius, the noise was gone! completely gone! Now I drove the car again, and it got chilly outside, and the noise was back. This makes me thing it's either EGR related or some heat shield or maybe even clutch related since the clutch is new?