This started about 3 or 4 months ago and I can't seem to find the source. It is definitely related to a certain vibration/sound frequency that is created at about 1800-1900rpm. It isn't present above or below that. Sounds like its coming from the center of the car and right about under the center console.

It sounds like a metal on metal vibration, like a heat shield, but I can't get it to stop. Hard to pinpoint because I can't get it to rattle in neutral or park, I'm guessing because the engine or exhaust doesn't reproduce the correct frequency when not accelerating under load.

Is there anything else that might mimic the sound of a heat shield rattle and only be present in a very narrow RPM range? Catalytic converter, maybe?

 

Or could be your exhaust rattling. There are several heat shields along the way... I dunno. Get under and look??

 

I've been under there 3 times but nothing looks/feels loose. Maybe I'm missing something, idk...are there any key points that I should be checking, or any way in particular to check other than just trying to manually shake things.?

 

check the honey comb section on the Y pipe just before the cat to see if it has broken free and one end or the other is one thought, there are as stated a number of heat shields in the area, one may be loose is another thought, and yet another thought could be engine ping or possible low oil pressure giving you that timing chain rattle sound.

Check your oil level
Check all the heat shields
Check the honey comb section on the Y pipe
and if available in your area move up to 93 or 94 octane gas

those would be a few of my thoughts

 

Check the small cross bracket too, before your axle-back starts? Is the exhaust close or resting on it?

 

Idk if its the same but i get a kind od knocking on the driver side at that rpm

 

I have the same thing. Been looking up the problem every once in a while and came to the same conclusions Ghost had. Could be one of the heat shield, but it could also be a timing chain rattle if you're burning oil. I have a feeling it's the timing chain due to low oil levels, if its the heat shield, you could try putting a bolt between your heat shield so there's tension so it wont rattle.

 

It's the timing chain hitting due to low oil, It basically means time for oil change that will temp fix the problem, that works for me, Try adding some oil and see if it still does it and it's around 1700rpm under load or deceleration...It's been talked about on here quite alot...