Explorers Gas Mileage and K&N Filters

In our area, K&N filters assure an early death to motors. Demographics means everything regarding filter selection. Bear in mind that a freshly service K&N will pass a lot of air, taking light dirt with it. Over oiling a K&N will contaminate the MAF.

Bang for bux... paper filters are just too convenient and I have much better things to do that bathe one of these abominations....... however, I do get paid well to service customers K&Ns...

Becasue your truck has eletronic feedback fuel injection, a K&N filter can't give better fuel economy than a serviceable paper filter; it just can't happen. Not possible. No way, no how. Plus, when clean, it passes more small dirt particles than a paper filter, and when dirty, although it cleans better, it's doesn't flow as well as a serviceable paper filter. And (unlike STP), the sticker won't make you go faster.

I have used the K&N in all my Explorers. I pull a Bass Boat at speeds up to 80 MPH and have logged miles in excess of 140,000. My engines were as good as new when I traded or gave them to my kids. Want 30 MPG get a Honda Civic, want class drive the Explorer. Remove the crank trigger and file the holes to advance the timing 3 to 4 degrees, you can also purchase a kit for this from any Mustang speed shop. Plug the EGR valve, need to swap vacuum lines, and install a cat back exhaust. No inspections in your state pull the cats and use Mustang MIL eliminators to keep the check engine light off. For $500.00 you may see a tick to

R> Hello all,

Thanks for everyone's help for this post. Thanks for the tip Ron although I think I will keep the mods for my 90 LX Coupe :)

J.H

Any way I can get some info on how this new Electronic Feedback Fuel Injection works ? This is new to me and would like to know how it works differently from standard fuel injection,

J.H

There's no such thing as "standard fuel injection." Just as there's no such thing as a "standard gas engine."

Fuel injection comes in many flavors; mechanical FI has a pump that pressurizes the fuel in a line, which then goes through a 'distributer' that routes the fuel to the various injectors, based on the throttle opening. Electronli FI takes much more than the throttle opening into account. It measures various parameters from sensors,and tailers the fuel amount to those parameters. Modern EFI inculdes feedback from exhaust sensors (O2 sensors), which tell the computer if the fuel mixture is lean, rich, or right on. In such engines, if the fuel mixture is too lean, the EFI will add more fuel; the air filter can't "fool" the EFI into making better mileage by reducing the filter's restriction. Not only will the feedback provided by the sensors keep the mixture the same, but the throttle plate itself presents far more of a restriction than the air filter will at any position other than wide open (how much time do you spend at WOT? Do you actually expect fuel economy at WOT?).

While some can be done to improve the efficiency of the engine, putting on a filter such as a K&N isn't one of those things, unless such a filter will actually improve efficiency; on the cars of the last several decades, this just isn't happening: the stock paper filters already flow more than the engine can use. What can be done? The usual first step is the improve the exhaust; simply making it bigger reduces backpressure, reducing pumping losses. Why don't car makers do this? Because it increases both costs and noise, two things the car buying public as a whole doesn't want. HTH.