When having a dirty airfilter will the fuel consumption is less than when the airfliter is clean

Question

i am just asking this question because while using a sport air filter k&n and so it is said that the ca will consume more fuel so if sport airfilter aloows more aiflow so the clean normal airfilter is allowing more airflowthan a dirty one then a dirty airfliter will decrease fuel consumption so cleaning my airfilter makes no sense then plz help me with that last time i travelled my car consued very low fuel i had 45mpg with a yaris but when i got home i went to the maintenance and they had to change the airfilter coz it was 25000 miles old

Answer 1

A dirty air filter will cause your vehicle to consume MORE fuel. This is because your vehicle needs to work harder to produce the same amount of fuel because of the restriction of air flow into the engine.

The engine is just an air pump. If you restrict airflow, it doesn't pump as much air, so it is less efficient.  

Answer 2

It dosnt make a difference really, yes you will use a lil bit less fuel with a dirty air filter but it will decrease the amount of power the engine makes thus making the engine work harder and longer which does more wear and decreases the life of the engine. Stick with the manufacturers air filter and your gas mileage will stay the same, about the same.

Answer 3

If you have a K & N, why would they replace it?

I have read a research document (independant test) using stock paper filters and assorted cold air type filters.  Amazingly, although the cold air filters like K & N were better, (yet some GM's had trouble with the filter oil contaminating sensors and causing problems), cleaning and oiling some of the cold air filters, and in comparison tests, not cleaning but only oiling the filters, the non-cleaned-oiled only filters, for the most part, had better flow than the identical units tested that were cleaned and oiled.  

Also, at the price of petrol, I would replace OEM air filter elements frequently.

If your shop replaced a reusable filter, and you are cool with it, I would go ahead and have them replace the headlamps, radiator, window motors and fuel injectors as well.  Nothing wrong with preventative maintenance.  Maybe after a few more visits, they will pickup and deliver you vehicle, leave you a loaner car and have you add them jointly to your bank accounts.  Soon, they can assign an employee to you full time.  You can appoint a room at your home and cook breakfast for them as well.  In return, you will have someone on hand to keep your car running and you won't even have to drive to the bank when you are invoiced, because they can access the joint account without inconveniencing you.

Answer 4

more air better fuel dirty air less fuel so anytime you replace something that is dirty you help keep your car running and the more you change oil and any  filters the longer the car will last

Answer 5

Fuel consumption is only based on how far you push the gas petal down.

Changing the air filter will not increase or decrease your millage. This ia a old wife's tale from back in the days of carburetor cars. Modern cars have sensors that monitor how the engine is working and adjust for variations in everything including small changes in the restriction in the intake (air filter). Most of us drive on paved roads so the amount of dirt that finds it's way to the filter is small so the filter will last a long time so filter changes are just done at intervals. Filter changes are mostly profit adders for repair shops.  

Answer 6

A dirty air filter means more fuel is being used, not less.  When the air filter is dirty, less air will get by which results in the engine running rich ( too much fuel ).

Answer 7

Replace the air filter.  The computer makes adjustments to the fuel injection to try to keep the mixture proper, however the engine has to work harder to suck the air through a partially clogged filter.  Reducing the power to the engine.

The EFI computer probably reacts by reducing the fuel quantity injected into air stream or cylinder to compensate for the reduced air flow.  If you have a lead foot, it will still not inject more fuel even if commanded by the throttle pedal, to avoid an over-rich condition.  (Pollution controls).

When you change the air filter, then a lead foot will cause more fuel to be injected, increasing the power and burning more fuel.  The cause of the MPG reduction is still your driving, not the clean air filter.  

Answer 8

the cleaner, the better. if the air filter is dirty, it can cost you at the pump.