Hey guys, so ive been trying to figure out exactly what this thing does for the intake. From what i can tell its got something to do with the EGR system in the car but i dont understand the reasoning for the massive size of it. The item in question is the large rectangular..ish looking black plastic box to the left of the engine in the picture below. The picture of the car isnt mine but the part is identical. here is the pic:


Thanks

 

Air resonator box, possibly with some vacuum reservoir effect. Removing it and patching the hole will affect noise levels and performance. Some say for the better, but probably for the worse. Aftermarket intakes generally don't have it and people don't seem to mind.

 

^ this.

It muffles sound so the intake isn't so loud. But it also acts as a reservoir of filtered air when needed, such as cruising at light throttle then suddenly putting the pedal to the floor. It works on the same principles as ARC intake boxes. Removing it won't hurt top end power, but doing so supposedly hurts throttle response a bit. But we're talking only 1-5hp/tq at most. The more modded a motor is, the more this part is unnecessary

Just a little note, your 98+ 1UZ-FE VVTI motor doesn't have EGR. That only exists on pre-VVTI motors

 

Thanks for the explanation guys!