Carbon filter in air filter housing cover problem

I suggest you replace the air filter housing cover so that the engine intake can freely breathe. (I don't believe the filter can be separately replaced from the cover.)

 

I think if you visualize the airflow up through the replaceable filter element and into the carbon filter, then flow to the right and down into the throttle body chamber, you will see that indeed all the intake air flows through this activated charcoal (carbon) filter. It's purpose is to capture vapors that attempt to escape the intake manifold past the throttle plate when the vehicle is off. Mine is getting pretty dirty and I wonder about the possibility of a flow restriction. Pretty hard to measure that.

 

You are correct that the purpose of the charcoal filter is to absorb hydrocarbon vapors emitted by the intake manifold.

However, as previously pointed out, the engine intake air will flow through that charcoal filter so if it is significantly blocked by "oil and gunk", that will obviously reduce engine output power.

 

What kind of material is the filter made of?

 

Then I would imagine it could be cleaned with something like mass airflow sensor spray.

 

Removing the carbon vapor absorber will surely allow more air flow ..
I have measured (with one inplace) about 20-25 g/s air flow from MAF ... about 2k-3k rpm ... seems kind of restricted .. ( filter and absorber dipped in water and partially dried very recently)
Measured using torque app . I have another cover with vapor absorber removed and will read and report the new flow.
Then I will spray some MAF cleaner on the MAFS and report changed flow (if any detected) --
then , when i find the K&N filter will install that and that should make a huge difference in flow ...

 

I tried years ago to install a K&N CAI on my 07. It did not like it at all. I think its because of its atkisson cycle.

Or maybe the maf did not like the increased airflow. It ran like the maf was bad. Probably a remap of the maf would fix it not sure.
All i can say is a direct cai swap will not work well. At least it did not for me. I hooked a K&N directly to the air box.

It was extremely loud for a little engine and made loud gulping noises when you tried to accelerate slowly. And ran very bad. Probably why it has that exotic intake piping with the intake sump box. More than just the steingholz effect i think.

The weird intake black tubing feeds the white plastic box in parallel and also has that other odd tube too the smaller black one that goes no where its just capped.

Lots of air flow dynamics engineering there. Brilliant.

Throw in the deep sump in the bottom of the intake manifold and you have a very strange little engine.

 

Helmholtz.

EEs get to build things with capacitors and they do useful things. Who said they get to have all the fun?

 

-_
I presume there is some ram -air effect when the car is going highway speed --- this probably gives a little mpg boost .. (a small boost of air pressure over atmospheric)..
It is alot of snorkeling going on so they are prob. doing that for the gain at a speed .. -- something over 30mph i would guess ..
The Camry hybrid has something even larger .. an 'air box' resonator .. i'll try and get a picture of that .. a very strange and volume consuming bird as well ..

 

I like cold air intakes have always used them was surprised how much the g2 freaked out when not using its factory snorkel.

Try it see if you have better results. Maybe I had something jacked up.

 

Do what experimenting that you want- so long as you don't disrupt airflow past the MAF sensor (that would cause the poor engine operation that edthefox5 experienced) . I doubt that any change to the air cleaner would have any significant impact on mpg. Really, until the air filter causes a measureable pressure drop that the engine has to work harder to overcome, you won't have a gain by using any aftermarket filter.

I also wouldn't expect any gains from "ram-air" effects. The Prius is all about matching just enough ICE output to move the car and charge the battery under whatever the current demand is. Stuff more air in and the ecu MUST inject more fuel to match- but if the computers decide that doesn't NEED more ICE output then it will just close the throttle some more.

Whatever you do keep detailed records of what you do and resulting mpg.

Posted via the PriusChat mobile app.

 

so .. g olden rule .. 1 change at a time .. the last change was the spraying of MAF sensor cleaner (by CRC) .. but then (a factor out of my control ) the weather changed .. about a 10 or 20 degree drop in ambient .. one would think the colder air would be more dense .. and another weather factor , rain .. cold water vapor doesnt carry much energy stand-alone like a fuel vapor .. -
: what i did see was about a 5 g/s drop in airflow after the sensor was sprayed liberally .. --
I am going to try OEM snorkel hookup next ..
The computer seems to keep load around 50-60% for most conditions ..(it doesnt vary too much)
My K&N filter is ~ MIA ... I'm not going to drop $40+ for a new one .. and the only gain would be some possible improved acceleration maybe; as mr. guy mann said .. not gonna gain much because the thing is tuned to keep things on the downlow for the low gas draw ... the steady state operation where the car gets it's good highway mileage , not a fast 1/4 mile or 0 to 60 time.
BTW: was just checking prices on k&N and there is HD Pro brand reusable for only about $22 .. for those of u wanting to give the higher air flow a shot ...

 

Yeah like changing gas .. takes the computer a minute to adjust .. --
But it should adjust ... if your computers and sensors are functioning ...

 

It’s a freaky little engine.

 

I actually filled with E85 again .. I'm not sure what will happen .. I have been doing this since last year .. I know the car is not cert. 'flex fuel' .. and there is less energy in E85 -- and suprisingly .. the place I fill at is cheaper than 87 octane E90 (or is it E10?) .. but I have seen the yellow pump at the same brand station but in the city having abotu a 10 cent higher price than 87 E10 gas .. methinks the M-A cycle engine can 'take it' better -- with all the exhaust overlap ... but i'm not sure about the rubber parts and their long term ability to handlle the 5% extra alcohol in the fuel ...

Today , I put the stock :OEM snorkel on the air cleaner so it was sucking in cold front of car air .. I think ? it fealt like more power .. but I dont have the HP widget on Torque-Lite ..
Ever so little more air seemed to be monitored but really seemed like same grams/second of air at a given rpm .. going up somewhat at a higher MPH due to the increase air flow onto the intake .. as far as mpg .. its up .. its down ... -- I guess i need to get a running ave. going for a given stretch of road ...

 

incidentally, .. for prob. the same price as a throw away filter., their are reuseable filters with a red filter material under a screen mesh .. they claim washable without the oil slick a K&N prescirbes and the benefit there is that the MAFS stays clean without any oil slick .. about $12-13 ....