Wow, just found out....

[A_A_G]

My brother in law has a 2006 Honda Accord v6 with 83k miles (bought it new) and just informed me that he has NEVER changed the air filter

. He changes the oil regularly but I was wondering what kind of damage could be caused by not changing the air filter?

 

[ZZman]

None really. It is still running.

 

[flanso]

Probably little damage besides increased fuel consumption. I have never seen a filter so stopped up that it caused the cylinder walls to be washed down, particularly on a fuel injected engine where there are oxygen sensors patrolling.

 

[JHZR2]

Higher pressure drop - lower fuel economy as the engine works harder to pump air.

Filters become more effective as they get loaded. You are balancing the "formation" of ever smaller, tighter pores/flow paths vs. higher and higher pressure drop.

Other than likely higher fuel use, no worries...

 

[KLowD9x]

I have never seen a clogged filter cause higher fuel consumption on a fuel injected engine. Sure, I have seen them cause black smoke and [censored] running on a carbed engine, but not FI.

 

[Captain_Klink]

worse is to get it replaced, but installed wrong. my Crown Vic had the filter put in wrong, I didn't notice it for 6 months. Unlike the oil filter, it can be fairly easy to mis-install the air filter. But if it was just never replaced - no big deal, usually if he takes it to Jiffy Lube, they shake out the dirt, and that's about all it needs. doesn't hurt to change it if the roads get very dusty, like in places that apply lots of sand in the winter, dirt roads, etc.

 

[BuickGN]

Dirty filters do not cause increased fuel consumption on fuel injected engines.

It's the equivilent to slightly closing the throttle blade. Reduced power, yes. Reduced mpg, no.

 

[froggy81500]

Originally Posted By: BuickGN
Dirty filters do not cause increased fuel consumption on fuel injected engines.

It's the equivilent to slightly closing the throttle blade. Reduced power, yes. Reduced mpg, no.


yes and no. Basically, having a dirty air filter won't specifically increase fuel consumption on a fuel injected motor because the computer is still going to try to obtain 14.7:1 mixture (stoich). So with less air, there will be less fuel added. Unlike carbbed motors that could not do this and that would be why dirty air filters on a carb cost you more in fuel. Carbs still meter the same amount of fuel regardless of the airflow.

Yes, less airflow on an FI motor does mean less fuel and less power. but it will also mean you have to step on it a little harder because of the lower power output. So it is possible that because you have to have the throttle opened more to get around that you might use more fuel in that regard.

 

[chambers]

If it's a paper filter then no damage as long as it's still intact. It most likely just plugged up w/ dirt and flowed very little, but it still keeps the dirt out of the engine. If it's an oiled cotton or foam filter and was loaded beyond capacity it would begin dumping dirt into the intact which would be bad, but I assume it's paper.

 

[Ken2]

If the back side of the filter element is dirty, that shows that dirt has been pulled through the filter.

Re-introduce your wife's idiot brother (sister's idiot husband?) to the maintenance chart in his owner's manual.

 

[JHZR2]

Stoichiometries are not the source of losses, per se. Pumping and thermal losses kill us compared to Carnot. We may just not notice it, but we cannot induce pressure drop and losses on the front and be as efficient. Try running a marathon in a surgical mask...