LaserRed01GT
Banned
Well, to be honest, it almost sounds like two different sounds. The low speed knock at idle, sounds like it's coming from the oil pan. The higher speed rattle is so hard to describe. Inside the car it sounds like a light metal rattle, under the hood it sounds like something more substantial. But it only happens when you float the throttle between 1500 and 3000rpms, and the noise doesn't speed up or slow down in that range. It's just there. Like a heatshield resonating. It just gets louder the closer to the 3k rpm you get, and then any higher in the rpm range and it disappears.
It does not do it under load. It does not do it while accelerating OR decelerating. Only at neutral throttle or very lightly accelerating. The fact that the frequency doesn't change with the rpms makes me believe it's not a reciprocating part, but the description of a rod knock really hits the nail on the head.
Oh, and "clackity" is a better description of the higher rpm sound.
Rod knock will increase as RPM increases. If this noise truly isn't changing along with the change in RPM's, it sounds like something is being resonated outside of the motor.
Can you get a sound clip?