The Great air filter debate - my findings & observations

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GlennSullivan

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Anyone old enough to remember turning the circulator engine air filter housing lid upside down on V-8 engines with a 4-barrel carburetor, to allow more intake air and enable a loud engine roar when the two rear carburetor barrels opened on wide-open throttle?
Unfortunately, I am old enough to remember all the tricks from those days. In my defense I had older sisters whose boyfriends got me started down the "burning gasoline hobby" path very early in life LOL.
 

JamaicaJoe

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Well, after reading many threads/discussions on the pros, cons, and opinions on the differences (if any) between different types/brands/tiers of air filters and whether or not they could/do have any effect on performance/mpg/horsepower etc, I decided to do my own little test and see what happened.

So my vehicle is in my sig, and with the following info, I proceeded:

A) 4x tanks of Premium 93 Exxon gas before & during the test, which is what I normally run anyways

B) Tires rotated & balanced, and oil/filter changed (Full Synth 5W-20 Mobile One) 2 weeks prior to test

C) 2 rounds of 3 mostly identical 200 mile trips, ~98% interstate and ~2% in-small city driving...

D) Maintained an average speed of 65mph by using cruise control as much as possible

Before the test, I was running a Fram premium air filter, and was getting ~11-13 mpg on average

For the test, I installed a K&N Premium 75K mile Oiled Filter, and am now getting ~17-18 mpg on average....

SO..... my observations are that I noted a fairly significant increase in responsiveness and acceleration during the test, especially when I had to step on it a few times to enter the freeway or to go around & pass some slow-poke doing 45mph in a 70 zone, and very quickly found myself going 80mph + in a 70 and had to let off the gas for a few minutes....

Even in the slower city rides, I could feel the beast wanting to take off like a young bull at mating time, and had to be real careful about how much pedal to give it :)

So there it is...... like it, don't like it, agree with it or disagree with it, but I'm hooked on my new K&N filter, at least for the time being, and will update this post in a month or 2 if there are any significant changes, good, bad or otherwise...
I would love to see that increase in MPG. My original truck was a 1993 E350 15 passenger van and the 13 MPG was making me sad. I bought a smaller, lighter 2001 EXPY and then still got 13 MPG. Then the adulturated gasohol scam cost me a mile or two. My flex fuel 2013 does not do any better. I think the results of your test call for some repeated tests, cleaned MAF sensors, fuel trim numbers compared. While we are at it what is best way to clean MAF sensor in a 3rd gen? Maybe I should be doing that?
 

GlennSullivan

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I would love to see that increase in MPG. My original truck was a 1993 E350 15 passenger van and the 13 MPG was making me sad. I bought a smaller, lighter 2001 EXPY and then still got 13 MPG. Then the adulturated gasohol scam cost me a mile or two. My flex fuel 2013 does not do any better. I think the results of your test call for some repeated tests, cleaned MAF sensors, fuel trim numbers compared. While we are at it what is best way to clean MAF sensor in a 3rd gen? Maybe I should be doing that?
Joe
What gears are in your 2013 Expy? All of mine are 4x4 3.31 with open difs.

I have a 2011 and had a 2014, both 5.4/3 valve and both produced around 14.X combo and 17/18 hwy.

My 2017 3.5/TT gets 16.X combo and 20.X highway.
 
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BigOleFordFan

BigOleFordFan

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I really don't know, so please just stop asking...
I think the results of your test call for some repeated tests, cleaned MAF sensors, fuel trim numbers compared
Well, I just did another 80 mile trip yesterday, and still got ~15.5 mpg, but about 1/2 of that trip was in the city with a fair amount of stop & go traffic, so I'm sure that had some effect, but still not bad...

Even though I thoroughly cleaned my MAF before the test, I have ordered a new one, since AFAIK the current one is the original factory part, and am curious what effect, if any, a new one will have on the mpg...stay tuned :D

What do you mean by "fuel trim numbers" ??
 

ManUpOrShutUp

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I'm getting 16.3mpg avg on my '11 EL with 219k miles. I have been running basic Motorcraft air filters since I got it.
 

Fastcar

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Figured I'd toss this in. 2024 SPP 3:73 gears 4x4. My wife does most of the driving. Probably 50% highway, 50% city. She runs it in sport mode most of the time on the highway at 75 mph. She is in 2wd in the city. She usually fills at 1/2 tank. Today she was running me to the bone crusher and I asked how the mileage was. She says 18.4, is trying a couple of different brands. Told her it was a putor and would adjust and doubted she would see a difference.
Full disclsure, red calipers, and the bigger engine. Stock air filter.
 

JamaicaJoe

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Joe
What gears are in your 2013 Expy? All of mine are 4x4 3.31 with open difs.

I have a 2011 and had a 2014, both 5.4/3 valve and both produced around 14.X combo and 17/18 hwy.

My 2017 3.5/TT gets 16.X combo and 20.X highway.
I will have to check the diff code on the VIN . I have a towing package, RWD.
 

JamaicaJoe

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Well, I just did another 80 mile trip yesterday, and still got ~15.5 mpg, but about 1/2 of that trip was in the city with a fair amount of stop & go traffic, so I'm sure that had some effect, but still not bad...

Even though I thoroughly cleaned my MAF before the test, I have ordered a new one, since AFAIK the current one is the original factory part, and am curious what effect, if any, a new one will have on the mpg...stay tuned :D

What do you mean by "fuel trim numbers" ??
The fuel trim is a value that you have to scan for in the Mode 6 OBD2. It has short and long term values. I was watching "the Wizard" on Tik Tok and he had a customers car, Toyota I think, new engine running great, no codes, but the Check Engine light would not go off. Turns out he had a K&N cold air intake and the MAF was not happy and the engine was actually running very lean which makes one wonder about what happened to the original engine.
 

DieselMonk

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Figured I'd toss this in. 2024 SPP 3:73 gears 4x4. My wife does most of the driving. Probably 50% highway, 50% city. She runs it in sport mode most of the time on the highway at 75 mph. She is in 2wd in the city. She usually fills at 1/2 tank. Today she was running me to the bone crusher and I asked how the mileage was. She says 18.4, is trying a couple of different brands. Told her it was a putor and would adjust and doubted she would see a difference.
Full disclsure, red calipers, and the bigger engine. Stock air filter.
If I drive it economical in eco mode on the highway, I get 22mpg. But short distance driving to town for work, errands etc. about 17.5mpg, regular gas, everything is bone stock on my Expy. Running the factory 22” tires it came with.
If I compare that to my old 2000 6L with a 4l80 back then, I got 17mpg as the best scenario on the highway and that went down to 11mpg in my short drive to town, work, errands etc. Putting a 21ft camper trailer on the back, it got 6mpg! Forgot to mention it had a 150l (39.something gallon) tank.
 
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