What is the black felt discs inside the cut out of the air intake assembly tube that goes to the air filter assembly? What is its function? Does it need to be replaced when I change my air filters? Thanks
welcome to priuschat! probably a prefilter, maybe just rinse them out? what does the owners manual recommend?
It is the resonator assembly, no maintenance required. RESONATOR ASSY for 2013 Toyota Prius|17750-37060
what does the resonator do? why is the open in the prius v ie get wet and dirty while the other prius versions its fully enclosed?
A resonator is like a tuned muffler. In this case it is used to reduce intake noise. On the 2010-11 Liftback, the intake tube leading to the resonator is made of rigid corrugated plastic. The Liftback and v from 2012 onward uses a wire reinforced fiber hose instead. I suspect the fiber hose is quieter, lighter, and likely costs less. This fiber hose is not very porous, so there is no worry of getting water or dust in through the sidewall of this hose. Besides, with the air intake only a few inches away, there would be no pressure drop across the fiber to pull any water or debris through.
So your saying the felt disc looking things in the intake tube cut out are not filter discs but a fiber hose?................About being quieter, I really dont think it is quieter (first prius but comparing to my v6 camry) when the engine is working. Its so loud going up a hill it sounds like the engine is redlining. I just justify it as a price to pay to get 400 miles for $35 (its $55 for 300 miles for the camry), anyone have a short ram intake and notice any degradation in performance? Reason I'm considering an intake is if its going to sound loud might as well make it louder.
First part: Resonators change the quality of the intake air flow. Sometimes they address eliminating "resonating" columns of air that might adversely impact optimum air flow through the intake system, others it's just to change the sound/tone of the air flow. Hot rod guys have been eliminating them for many years them to get that peculiar deep toned sound of air rushing into the intake. Second part: Not having seen other versions, can't begin to answer.
Yes, the felt looking thing is a hose made of fiber. You would have to compare the intake noise level to a 2010 or 2011 Prius with the corrugated rigid plastic hose. Remember that the Prius engine is Atkinson cycle, and has a significant amount of reversion into the intake tract. Also, to reduce pumping losses, the throttle is opened quite a bit under light load conditions. These would increase intake noise over a conventional car. I am also curious about how the engine would sound with an aftermarket intake.
