Air filter and mpg's

A coworker has a Jeep Renegade and changed the stock air filter for a K & N air filter. Claims the Jeep now get 4 miles more per gallon on the highway.
Has anyone tried this in their Tacoma?
Mine is a 2017 2.7 manual 4x4 Access cab.I'm thinking about giving it a try.

 

You will get no gains in MPG's, HP, Throttle Response. You basically get nothing, don't waste your money

 

He's lying--if using a different air filter could improve mpg by that much why wouldn't Chrysler or Toyota use them as OEM, vastly improve their Corporate Average Fuel Economy, and save a whole bunch of money in CAFE fines?

 

Only thing the K&N will do is make more induction noise and foul up your MAF sensor.
Butt Dyno will post good numbers though.

 

Re: K&N, I wrote this 12-1/2 years ago--my opinion, and nothing about K&N filters, has changed since then...

 

Hopefully your coworker doesn't do the budget for your group. His math skills are suspect.

Unless his previous filter was an old Tacoma World t shirt or something.

 

There is a Honda forum that I used to frequent with a well known tuner on there that would test high flow filters, cold air intakes and the like on a dyno. Surprisingly most of the stuff that was marketed for "gains" actually posted lower numbers than stock, mind you this was all prior to flashing the ECU.

 

I used K&N filters for years on carbureted dirt bikes and street bikes. When done in addition to rejetting, I saw noticeable performance gains. Without jetting changes, I saw no improvement in performance.

I put a K&N air filter in my stock 2000 fuel injected Road King and had huge driveability issues. I replaced it with an OEM filter, problem solved.

I put a K&N filter in my 2002 Chevrolet Silverado 1/2 ton with V8. It caused the motor to run lean and the air filter oil eventually fouled the throttle body valve. I cleaned the throttle body with CRC and replaced the K&N filter with an OEM filter, problem solved.

Hold onto your money and use it to buy fuel.

 

The only thing high performance about K&N is their marketing dept.

 

I lost mpg's using the oiled TRD filter. Contaminated my MAF. Stick with the OEM paper.

 

Lost on many is that the air flow into a n/a piston engine is not a steady stream but rather a sequence of pulses, each having a lower than ambient pressure head, a near ambient pressure body and a higher than ambient tail--and each having mass. The velocity and frequency of the pulses is a factor of engine speed, throttle opening, air density and a number of other factors. Therefore the intake is much more than just a "bigger is better" pipe but is rather a tuned conductor designed to maximise intake air flow at all engine speeds/throttle settings/air densities/etc.

The major automakers have test facilities and equipment for developing intake (and exhaust) systems that aftermarket makers only dream about. In the end even the best aftermarket intakes. Those that do not rob power--overall or at certain engine loads ("suck-outs") because of poor design/engineering--provide nothing but increased intake noise which though having a very powerful placebo effect doesn't really do a damned thing except lighten your wallet.