Just removed Hydrocarbon filter

I just removed mine, pulled the EFI fuse and removed the carbon filter. Took a couple minutes. I just had a Magnaflow 12586 muffler installed on Wednesday and I already have an AFE Pro Dry filter so I should be good to go. Since the Muffler the 4Runner definitely has opened up some. Cant wait to see what this does.

Thanks everyone for this thread. I read the first 9 pages, went outside, pulled the Carbon filter out and I'm now posting this. Thanks again.
 
I read the first 9 pages, went outside, pulled the Carbon filter out and I'm now posting this. Thanks again.

Nice! That was me last night. I read this thread and went out to my garage at 9:30pm to pull out the filter. The wife thought I was nuts, but I had to do it after reading this thread.
 
After reading this I went out an removed the filters from my T4R and wifes FJ.
Then thinking about the discussions on this, I realized that it is not going to be any problem to run without it.
Does Toyota put the carbon filter in the TRD CAI?

Everybody that has installed an aftermarket CAI has essentially removed the carbon filter and their rigs are running fine.

I think this thing is a political response to some California requirement.
 
just noticed mine today for first time and found this thread - curious, if toyota installs it because "the law requires it", then if we remove it, will the vehicle pass state inspections?

what got me looking at it, was at the state inspection last week, toyota mechanic told my wife the air filter was close to needing replacement - i had just changed out the normal paper filter so i took a took to see wtf he was talking about when i noticed the hydrocarbon filter

i'm in Virginia, so passing the state inspection part might be state related, but still curious what folks know on the subject

TIA
 
just noticed mine today for first time and found this thread - curious, if toyota installs it because "the law requires it", then if we remove it, will the vehicle pass state inspections?

what got me looking at it, was at the state inspection last week, toyota mechanic told my wife the air filter was close to needing replacement - i had just changed out the normal paper filter so i took a took to see wtf he was talking about when i noticed the hydrocarbon filter

i'm in Virginia, so passing the state inspection part might be state related, but still curious what folks know on the subject

TIA

Where I live we have to have an annual emissions test and mine passes without my hydrocarbon filter. I think California is the most stringent as far as emissions requirements and there are people who've done this in California as well.
 
thanks but if what seems to be the wisdom that it's purpose is to prevent "backflow" of fuel vapors then i doubt it could effect emission testing, bad, good or removed

i suspect the toyota mechanic that performed the state inspection was aware of the hydrocarbon filter and using the state inspection to sell parts and legally he wouldn't be wrong in checking emission system items. Now the question is, are they common on other vehicles, ie fords, chevy etc - cause if they are, then i suspect i'll have the same problem at next years state inspection, wherever i take it

just left the orig toyota dealership (Haley Toyota in richmond, va) - last year at state inspection (vehicle had 68k on it, 7 & 1/2 yrs old) he indicated the rear drums and shoes were 'barely legal" but would pass that inspection, but definitely not make it to next state inspection. This year, in getting ready for the state inspection, i purchased new shoes and still had the orig toyota drums from when they installed the TRD kit on the truck (for some reason the mechanic that installed the TRD components put the orig rotors, calipers and rear drums in the back of the truck). When i pulled the drums, the shoes were nearly new, very little dust in the drums and the drums were also in near new condition. I had found the adjusters fully loose when i pulled them, which means for 7-8 yrs we'd driven that truck with no braking action at the rear. The mechanic that had installed those TRD drums/shoes had left them loose back in 2004.

So to compound his mistake, at last years state inspection, the mechanic tried to sell my wife drums & shoes - she'd put him on the phone to me so he could explain to me what he was suggesting and he clearly stated he'd pulled a rear drum (which i doubt).

I used to mechanic at a then Datsun now Nissan dealership back in the 60s/70s so i know what some mechanics pull or try to pull but we're talking $700 + labor for the rear drums & shoes - kind of pissed me off.

oh well, rant switch off - back to point, it might serve me to try to find a replacement upper air box housing from a 2004 tundra with lower mileage on it so it will pass next year, wherever i go for inspection. In the meantime i'll cut this one out
 
i suspect the toyota mechanic that performed the state inspection was aware of the hydrocarbon filter and using the state inspection to sell parts and legally he wouldn't be wrong in checking emission system items.

State emission inspections are different from state to state. We've only had them here in NH for 4 years now. And the emission inspection consists of just hooking up an OBDII scanner and reading the codes. NOTHING ELSE.

Removing the hydrocarbon filter may or may not fail an inspection....but what you run the risk of a premature catalytic converter failure. That can be very costly.
 
if the hydrocarbon filter is, as folks have suggested, a filter to cleanse fuel vapors from backflowing into the atmosphere when engine has shut down, i'm not sure what it can contribute to emission or it's not being there can contribute, - ie, how can it effect the catalytic converter much less damage it?

just curious
 
don't take the bait about the cat failure (must be an early April fool)

raw fuel escaping into the atmosphere from the intake is indeed an emission, just not an emission from the tailpipe
and that raw fuel vapor can only escape for a short time after engine shutdown...
 
Just removed my HCF, and am currently resetting the EFI computer.

According to Fuelly, I have tracked 21 fill-ups since 9/15 (holy ****...)

Best calculated MPG - 18.2
Average calculated MPG - 17.0

I have finished a tank with 19-20 on the dream-o-meter.

I will report back after a few tanks and we shall see if I net any results from this.


Possibly one of the easiest "mods" I've ever done...
 
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Just removed my HCF, and am currently resetting the EFI computer.

According to Fuelly, I have tracked 21 fill-ups since 9/15 (holy ****...)

Best calculated MPG - 18.2
Average calculated MPG - 17.0

I have finished a tank with 19-20 on the dream-o-meter.

I will report back after a few tanks and we shall see if I net any results from this.


Possibly one of the easiest "mods" I've ever done...

Thanks for getting back to us. :llama:

Anyway, I'm REALLY going to post an update to this, so this is the "before":

iCKVjCel.png


I pulled the HCF and drove to the station for a fill-up. Will report back.
 
And here it is.

The first fill up after HCF delete was dismal, but maybe the ECU was adapting or something. Needless to say I was pretty unimpressed.

Keep in mind that the last fill up was pretty much run almost every morning and afternoon with the AC on, whereas the previous ones had it only in the afternoons.

This needs to be looked at over time, so I'll keep tracking. Lift was done Saturday, then 265/70/17s were done the following Tuesday, so they could affect results. I guess we'll see.

gYxFyTnl.png
 
Yep. Guess I haven't been on here in a while.

Gas mileage is unchanged. In fact, this Winter was horrific, think I averaged about 15. I even installed a K&N filter.

Best tank is still 19.3 (matched recently). My worst is around 12.

My overall gas mileage has decreased from 17.2 to 17.0 since I removed. Not much change in the way that I drive.
 
I just pulled mine. If you haven't done this you should. No MPG feedback, but acceleration was significantly improved.

Now to just figure out a way to remove the cats and still pass inspection....ha.
 
Sure this is a year old... but I am paying a lot less for fuel than when GWB was president. Is this something that will kick in when he's been president for 2 years? 3? 4? 8? Or are we still waiting for it to happen? ;)

Oh, but to be on topic. I just removed mine and did the reset. I bought the thing and it was reading 4 MPG. I think they must have started it up and let it idle on the lot everyday for the month they had it. I never reset the mileage and it never got above 12 on the computer. I reset everything and removed the little filter doohicky and in a lot of driving around today I was reading between 21-23 on the computer. I have a light foot, no junk in the truck to weigh it down, and had the AC off. So far so good. Thanks for the tips guys. If I don't notice a huge difference I'll probably put the filter back in... just because I guess Toyota put it there for a reason. But knowing Toyota like I do, I'm not exactly sure if they even knew why. Haha.

How are those gas prices now?
 
Near $2.35 a gallon in most places around here. Plus I own a share in an oil well that my grandfather left to me, so get a pretty ridiculously pricey check quarterly. On top of that I make more money for working less hours and my pension payout just jumped last year. I'm excited. How are fuel prices there. When I bought my FJ Trail Teams in May of 2008, I got it for well below cost because gas was at $5.00 a gallon here. Now I just got back into a 4Runner Sport V8 (2008) which is my favorite vehicle ever, because gas is cheap and I can afford to commute it. Sure is nice having all of that torque in a relatively small package. I feel like I'm driving a sports car that was designed for my height!
 
Near $2.35 a gallon in most places around here. Plus I own a share in an oil well that my grandfather left to me, so get a pretty ridiculously pricey check quarterly. On top of that I make more money for working less hours and my pension payout just jumped last year. I'm excited. How are fuel prices there. When I bought my FJ Trail Teams in May of 2008, I got it for well below cost because gas was at $5.00 a gallon here. Now I just got back into a 4Runner Sport V8 (2008) which is my favorite vehicle ever, because gas is cheap and I can afford to commute it. Sure is nice having all of that torque in a relatively small package. I feel like I'm driving a sports car that was designed for my height!

Sounds like life is a hoot for you. Congrats. I wish things went on track like that for me. 2 major things happened to me this year as I reflect. I broke my shoulder requiring surgery a couple days before my first baby boy was born. I had surgery the week after he was born. Couldn't stand the sound of bones grinding against each other. A mother good thing was I picked up my 4th gen. Plenty of ups and downs this year for me.

On topic. No changes for me after hc filter screen removal. 16ish mpg on average. Not bad with the tires I have.
 
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