I can explain exactly how it works.. but the key is in the calibration of it based on logging data in the real world with the modifications in place...

The device itself just takes the RPM signal and current reported MAF voltage as input.. Looks up and adjustment value in the cal and reports that to the ECU instead of the normal value.

sorry to resurrect this thread-drift, but i was thinking about it some more...

that is, of course, startling. can you provide any more details on the Taco? i'd sincerely like to know.

in looking more closely at the test, the specific parts it compares are complete CAIs for diesel motors — pitting an S&B CAI with both oiled and dry media filters -vs- an aFe intake with a dry filter. it's not a pure comparison of filter -vs- filter in the same intake... there's no accounting for discrepancies in the designs of the intakes themselves. also, while i understand the "dusting" issue is far more prevalent with domestic diesels, the fact that this is one manufacturer's paid study in order to one-up its competitor is not without a worthwhile mention.

further on this, TRD oil filters also use a 100% synthetic filtration media and tout improved filtration -vs- OE paper filter elements. that claim could equally be construed as "fishy", but Toyota sells and guarantees them just the same. just another point to consider...

finally, as it happens (and prior to this thread) i recently cleaned my aFe Pro Dry filter and disassembled my TRD CAI, cleaning everything, including my throttle body and MAF, while it was all apart. there was not much to clean downstream of the filter, to be honest. the TRD tubing from the airbox to the TB was spotless, as was the MAF, and although i cleaned the TB for good measure, even after 8 years in service without cleaning there was not much elbow grease to be expended. the only thing there really was to clean was some sand in the bottom of the intake box (normal for me; only now plugged that gap along the rubber grommet in the TRD lower airbox's driver side mounting point) and the filter itself. both were in normal condition according to my experience with this vehicle and the environment in which i run it.

i also did another UOA just 2 months ago and my silicon readings were exactly where they've always been; normal. based on this thread, i reached out to Blackstone and asked them for comment... their response:

"We use silicon to gauge air filtration effectiveness, using a spectrometer to look for extremely small particles. Microscopic pieces of dirt will add to silicon, and a silicon reading close to average is what we look for. That's been the case with your Toyota so far, so the air filter you're using appears to be working well. Poor cylinder-area wear is a common outcome of dirt ingestion. That is metals like aluminum and chrome from piston and ring wear, or iron from the cylinder walls. We more often find dirt from improper filter installation, or an intake leak downstream of the filter, than we do from an issue with the filter itself."

i'd genuinely like to hear more about the Taco whose engine Toyota claims was destroyed solely by an aFe filter. my hands-on, empirically-supported experience seems to suggest that there may be something more to that story—something fishy—but i remain curious and always eager to learn.

Agree 100% these cases are almost always something where the airbox coupler was loose or the airbox was literally full of dirt. I really doubt it had anything to do with the filter not filtering properly when used as recommended by mfg.

I don't have a ton of details. But the basics are; engine failure on cyl 5. iirc. Tacoma has 55k miles. No explanation of visible dirt in intake. Dealership backed up by Toyota corporate voids warranty due to AFE filter. There's more on Tacomaworld.

I don't think it should be a surprise that a filter with less fine filtration media allows more dust and to go by. it's kinda basic physics of fluid dynamics. The only way to make small holes flow more air is to either put more of them in (more surface area of filter media - unlikely given the pleat size and spacing is already optimized), make them shorter in tube length - thinner sheet of filter media, or make them bigger. My money is on the last one. K&N are the same way. They void your warranty too. (Yeah, they say they don't - unless you go off road... then they do.)

This is something pretty easy to test yourself if you're really wanting to compare them. All you need is the stock intake housing lid removed from the vehicle, a shop vac, some fine dust, and some duct tape. To do an accurate measurement you'd also want a very high precision scale. But you don't need one. Just put a secondary filter in before the shop vac and watch how much goes through. It'll give a pretty good idea of the relative effectiveness. I'd try very fine powders - like flour or Portland cement would be a good choice to test. Ideally if it is colored will make it easier to see in the secondary filtration. A dyson type vacuum would probably do a pretty good job too if you clean it really well before each use to see how much flows through.

Since I am a regular on TW I can say that thread was a he said she said my cousin said my former dog owner said.... In fact the thread was closed because there was zero proof this even happened. It was just someone posting that it happened and no one backed it up.

As far as URD maf cal it only works when in open loop. Lot's of info on XRunner underground as it's been around a long time with some dyno's to support it.... Still waiting to see what OVT will offer for these trucks if they ever get caught up.

Can you provide links. I could not find anything but did not try hard.

I've heard these claims in the past about filters many times, but for some reason they can never be backed up with facts. Its always some guy....or saw it somewhere...

I think it is more than just restriction = better filtration. The the type of media is a big factor. Comparing paper to paper.. this may be true.. But synthetic materials and oiled filters behave very differently in how they trap particles. It's more of a cling effect. You have to keep them clean to have proper filtration, and the oiled ones have to have the "right" amount of oil to work.

Now if the Tacoma guy put in a dry AFE filter and never cleaned it... and had an aftermarket bumper and ran in dust all the time... I can see it dusting the engine. Not syaing it can't happen, but just using a little common sense and care usually prevents it. There is clearly some information missing from this story.

the original thread was apparently a dumpster fire so mods closed and deleted it. this thread here was inspired by it, and references the original throughout... https://www.tacomaworld.com/threads/...filter.526401/

according to it, the Taco that was denied warranty was already on its second motor? (it's unclear to me if the second was a rebuild on the original or a new crate motor or what...) and he presented the Taco for another major warranty claim with an "engine bay full of mud" at 55k miles... Toyota denied the repair and pointed at the air filter as the cause.

it certainly seems as though there's more to this story than an incredible tale of an aftermarket air filter detonating an engine. if someone "was there at the time" please chime in and flesh out the details of this incident for those of us who weren't.

and apparently the owner had taken and posted photos of the same Taco perched on a rock in the middle of a lake?

LOL, there is always a backstory on these denied engine warranty claims.... but this is how the internet legends get started.

Just a thought as all of use would like to know the facts. Perhaps we can have the TACO owner post here with details of what happened?

To the OP this is great and thank you. I spoke to my very trusted mechanic about doing a COI either AFE or K&N and a Borla Cat back exhaust and he said well you can do that but if you don't do anything to the MAF sensor then the ecu and engine will actually work against the mod. you basically need the MAF to tell the ECU what you've done or, like on other threads on here, you'll find potentially less power and worse fuel efficiency. I found a JET MAF that claims to do just that, but having been to the website of the one you put in, knowing you can send them exactly what modifications you have done makes quite a lot of sense. it's my understanding that these three modifications really work best as one combined upgrade. I thought I'd let my engine break in a little more as it still has less than 5k on it, but this is very helpful. it sounds like you've already got the COI AND the CAT back exhaust, is that correct? thanks again!!

Yes, on the CAI and Borla Cat. Not available at the time was the URD CAT back at 3"OD. Suggest you look at this as good alternative to Borla. Not that I am unhappy with the Borla.....

Love how you try and say 'hey guys check out this cool thing' and you get sidetracked into a debate about air filters or some such.

Can debate it forever and have been...
THE Truth about Aftermarket AirFilters!


I like the URD MAF too!
I cant say as to how the MAF works but it does.
Seems like it even shifts better.
I hit 305hp on the scanguage2...I know its not real hp measurement...we don't have to debate that here, thank you.

/cheers

Depends how you look at it. Others took the post down the road of Wet/Dry/OEM filters. URD MAF works great.

My experience after running them for awhile (Wet/Dry) No Problems

That's what I meant, I have had no issues with K&N either.