Weird rattle under acceleration... 2k RPM...

[99blkx]

2001 MP3. 160,000 miles. Mostly stock but has exhaust (CS) and a few other things. Trying to diagnose this noise. It only happens when accelerating from about 2000-2500 RPM. Usually when warm and all gears. Never heard it in neutral or reverse. Sorry for the wind noise. Thoughts?

https://www.youtube.com/watch?v=qd8mfuTJLf4

You can hear it very faintly at about 6 seconds in this video and see RPMs about 2k.

https://www.youtube.com/watch?v=FntVgQxCpbI

Also... Runs fine otherwise. Pulls decent. No smoke. Recent oil change.

I've done some searching and reading. Could be a heat shield or a spun bearing or the butterflies or oil starvation.

 

[concept]

The easiest way to diagnose is to have your car on a lift so you can tap on various areas of the exhaust. You can always take it to a muffler/exhaust shop and watch a tech do this. They probably won't charge you anything. And if the culprit is a broken weld, the cost to weld shouldn't be too much.

 

[99blkx]

More investigation... It won't do it in neutral or while rolling with the wheels off the ground. Resistance is required. It also stops at full throttle. Only at partial throttle normal driving throttle does it happen. Still stumped. Hard to diagnose and not willing to throw parts at it...

 

[WyvernX]

I had a similar rattle on mine that only happened around 2-2.5k RPM. I haven't heard it since replacing the muffler.