[cliffsta]

Hey guys, I’ve seen removing the carbon filter discussed several threads, but I haven’t found a proper write-up, so here goes nothing.

As with any DIY, you the owner assume all responsibility, I’m not liable, etc….

Skill level: 2
Time: 15-20 minutes

Tools needed:

Phillips head screwdriver
Flathead screwdriver (one small and one large if you REALLY want)
Side cutters and/or needle-nose pliers

Begin by unplugging the sensor on the intake tube by sliding the light grey locking mechanism OUT from the tube, then pinching the tab and sliding the sensor off.

Undo the four tabs holding the intake box top to the bottom of the box. There is one on the front, one on each side, and one on the back near the bottom.

The cable for the sensor is attached with a reusable cable tie. To release it, use a small flathead screwdriver to depress the tab under the tail of the tie, and push the tie back through the loop. Set the cable and sensor off to the side.

With your Phillips head screwdriver, loosen the clamp holding the box top to the tube. Back out the screw until the tip is near the end of the bottom half of the clamp. Then wiggle the box top out of the intake tube by pulling towards the front of the car. BE CAREFUL to not damage your factory air filter. Remove it from the box if you feel you can’t remove the box top with the filter in place. The box top should wiggle free of the intake tube without much effort.

With the box top out of the car, we can focus on removing the filter. The carbon filter is held in place by four plastic pins that are basically molded to the filter itself. With your side cutters or needle-nose pliers, carefully pluck the tops off of these pins.

Once you get three of the pins removed, you can wedge a small flathead screwdriver under the edge of the filter and pop it out of place, dislodging the last pin. I say this because one of the pins is in a very narrow channel and is difficult to reach even with needle-nose pliers.

With the filter removed, take your side cutters or pliers and trim any leftover material from the four posts that held the filter in place.

Voila! You no longer have a carbon filter in your filter box!!

I’m hanging on to my filter just in case I need warrantee work on my car. It can be reattached with screws or a small L-bracket inside the box. And I always like to hang on to all the junk I remove from a vehicle as treasures from DIYs

I hope this DIY is helpful. Please feel free to ask questions. I have higher-res photos if anyone has questions. This is pretty straightforward. Engine noise increased marginally (which we all like!) can’t really say much about power increase because the roads are wet. Will be curious to see what MPGs look like going forward.

-Cliff

 

[hydroponik]

Great write up, however I thought this filter would not be re-attachable once removed since the bolts are molded into the intake?

 

[cliffsta]

You could fabricate A Bracket if you absolutely needed to put it back in. Or run some screws through the frame. Can you reattach it exactly as stock? No. But you could pretty easily get it back in there well enough that a dealer mechanic wouldn't even know if it had been out. I bet most dealer mechanics wouldn't even know it was supposed to be there.

 

[Cobra Jet]

What exactly is gained by this mod?

 

[Videopho]

Allow more air flow if I have to guess, meaning more throttle response along with a couple hp gained.

 

[84FordMan]

Depends on what you want, but I had to bow to Hyundai in their wisdom, at 46,000 miles, never had the throttle body cleaned, despite this, the throttle body looks as virgin as mile 1. No carbon or oil build up at all.

 

[cliffsta]

84fordman: This filter isn't here to filter incoming carbon, its here to catch escaping emissions while the engine is off. Though it is good to hear about your throttle body! And that's a ton of miles in three years. That's about what I put on my Accord in 5 years LOL

 

[Kapura]

just go wth short ram or cold air

 

[GTIGuy]

Okay, just did this mod today

ABSOLUTELY this adds power you can feel, and improves drivability.

If you're concerned about warranty issues, simply buy a stock airbox (you only need the top) from someone that's done a cold air intake, and you simply undo the altered one putting your stock airbox top with the charcoal filter in it back on. It'll take 10-15 minutes your second time you do it. Note you'll need to unbolt the air sensor from one top and bolt to the other ... we're talking 2 screws and a little wiggle to overcome the tension of a rubber seal ... easy easy for even the most mechanically illiterate.

I did not pull the negative battery terminal as one person on the forum has suggested .. the computer will make the adjustments. Think of driving up high mile high in the mountains (thin air), and then back at sea level (dense air) ... you don't need to force a reset, the computer handles it. Or for that matter, driving with a very clogged air filter and then replacing it ... same thing, don't need to pull the battery terminal to force a reset.

KUDOS TO CLIFSTA FOR DETAILING THIS. The hardest part was the little plastic hose clamp that holds the sensor cable to the airbox. I was about to snip the whole thing off and then replace with a zip tie, but there is a small release tab beneath the plastic clamp that you depress and then try to hold it there whilst you push the tail end of the plastic hose clamp through. This is explained in the DIY, just get some light in there and a small enough blade screwdriver and trial and error will take care of the rest.

If you buy an second airbox top to modify, don't even bother with this bugger and just use a zip tie through the hole in the tab on the box top that's available when the anchor for the hose clamp and the hose clamp itself are removed. If you need to put your unmodified airbox top back on to go to the dealer, then use the official plastic hose clamp thingie.

On the air flow sensor connector, the grey plastic locking tab removes completely, just press a finger nail on the raised tab surface, keep pressing, and use your other hand to grip the outermost ridged part and pull. With this grey lock tab removed, then you can easily remove the black sensor connector by pushing down the small levered tab on top and holding it up while pulling the connector off.

Enough of that. Onto results ...

The car has noticeably more pull, especially down low. I told myself to be skeptical, but a thorough drive using various rates of throttling in convinces me this is significant. Also, where the car was jerky a bit in trying to moderate the throttle in 2nd and especially 1st gear, you can now actually do that. It's as if the engine wasn't able to get in enough air initially, and you had to throttle more to force it, then when it takes a breathe in, well, at that point it's playing catch up and was creating the herky jerky-ness. I was in the habit of pushing in the clutch to coast in stop and go in 1st, but now it's capable of being moderated with the throttle. Much nicer for the slow stuff.

That charcoal filter is bogus EPA overkill for outgoing gas fumes, stupid. As others have observed, we'll burn less gas from better mileage, far offsetting the occasional release of gas through the intake when shutting down the engine. GET RID OF IT!

This sounds questionable I realize, but over the years, I think I've developed a pretty good butt dyno. I'm going to call the K&N plus charcoal filter delete a 9-10ish hp gain. Whatever it is, you definitely feel it. It's definitely more than a 5.

The stock airbox is a good design, brings in cold outside air via a small ram inlet, I'm happy with the system now, not too motivated to do a cone filter on a stick the dealer is going to razz me over. Plus, I'd rather bring in the coolest air I can, and to me, that's what's outside the car, not from the engine bay.

The perfect mod, cheap, easy, fully reversible, better power and mpg.

Also, notably, K&N now has an insert in their box with a phone number for anyone trying to deny warranty service due to their filter ... K&N will speak directly to them. Note you can get stupid if you heavily reoil a used filter and throw it in your airbox. I've always just bought a new one at 50k miles, but if you clean and reoil yours, be sure to let it sit flat for 24 hours on newspaper/whatever so any excess oil can drip free.

DO THIS MOD!

 

[cliffsta]

Thanks mate, I'm glad the walkthrough was useful.

Live long and prosper.

 

[superslow_gen]

this will b nice to kno for future references, thanks.

 

[I R Moose]

Glad to see a nice free proven Gencoupe diy, I'll be doing this tomorrow morning

 

[GTIGuy]

Glad to see a nice free proven Gencoupe diy, I'll be doing this tomorrow morning

Let us know what you think.

Edit ... Interesting info from a Toyota Master Tech on the carbon filters. Another governmental overkill solution IMO.

"All newer cars have these Carbon filters inside the intake box (they are for emissions). The Government and EPA are very concerned about carbon emissions and raw gas vapors from car and trucks. When you shut your Yaris off, there will be unburned fuel inside the engine and these vapors will make their way up to the air filter box housing and outside to the air. This carbon filter you are wanting to remove traps the unburned fuel and stops it. Then when you start the car, the natural aspiration will suck these carbon molecules trapped by the carbon filter back into the engine to be burned, thus reducing you cars emissions."

http://www.justanswer.com/toyota/4xv1p-toyota-yaris-2008-toyota-yaris-inside-filter.html

 

[I R Moose]

Let us know what you think.

haha, completly forgot i posted in here, been driving w/out the carbon filter for about a week know and got the same results as everyone else, love the slightly deeper exhaust note and the better throttle response.

Definitely a mod id think everyone should do the second they get there Gen.

 

[Russ140]

I just did this mod, thought I'd share an idea...I used a dremel tool with a flat faced grinding stone to get the carbon filter out. I selected a grinding bit that fits in the channel where the pins are, and kind of used the dremel like a pencil eraser, gently grinding the round part of the pin flush with the filter housing. After "erasing" the pin heads, a gentle pry with a flat screwdriver lifted the filter right out. Nice thing is the remaining posts in the housing are nice and flat on top, and sit flush with the surface of the carbon filter frame. I can easily replace the carbon filter if needed, as it slips perfectly back onto the posts. I would probably just dab some black permatex on the pin locations to make it look "original" to any prying eyes...
I did take some pictures, but I guess I have not posted enough to be allowed to post them.

Like the other posters I feel a better pull at lower RPM's which I hope translates into a little better mileage on the highway. It also feels good to remove something that apparently serves no purpose other than provide some Eco-Nut something to feel important about.

Doesn't hurt that it sounds great too...!!!

Thanks to cliffsta for a great mod!!!!

Russ

 

[ShaverZBT]

I'd love to do this mod but don't want to chance it failing smog since the charcoal filter is required by law here in California. I see Russ did this mod...perhaps maybe.

 

[Russ140]

All I know about the function of the carbon filter is what was in GTIGuy's post. I'm going to leave the carbon filter off for my smog test (won't be for a while) under the assumption that they do not test for escaping gas vapors on shutdown. If I fail, I'll go home and pop the carbon filter back in and retest.

Of course I would never REALLY drive my car without the carbon filter, as that would probably be ILLEGAL, so all this is just hypothetical...

BTW, I hope you all had a good Memorial Day! Huge THANKS to all our Vets!!!
(Hope that's not against a Forum Rule, if so sorry...)

 

[LandoAWD]

This is silly.

 

[GTIGuy]

Glad to see others are doing this mod, and enjoying the benefits. This charcoal filter is nothing more than the plastic accordion around the fuel pump neck at the gas station to catch fumes. The silly part is, I'm getting about 1 more mpg without the filter, which means I'm throwing less carbon into the atmosphere by removing this device.

Russ140 ... I'd be shocked if they did some sort of gas fume sniffer test out the front of your car. Holler after you pass your smog test ;-) ... good idea on the dremel surgery to make reversible without getting a new airbox lid like I did.

 

[ShaverZBT]

Ok this has to be a 3.8 mod only. I have the 2.0T and this carbon filter doesn't exist.