The word "dirty" is a relative term. Would you consider this engine air filter dirty enough to warrant replacement? I ordered one anyway, but wondering what everyone on CL considers as "dirty" This filter supposedly only has 10k miles on it. What does everyone think?
Thanks

 

Me personally, no. I'd vacuum/blow out the debris and reinstall.

 

i would do the same as above.

 

I'd keep in for another 5k, probably not 10k

 

I change it every 10,000 miles, regardless of the appearance. I consider it a cheap $20 investment to not even have to think or worry about it.

 

A "dirty" filter is better at filtering than a brand new one. 10k miles is too soon in most cases.

 

That's about mid-way dirty to me. Blow air or smack it a few times to dislodge the larger particulates and reinstall.

 

No way I'd run that filter - that's pretty dirty - I'd replace it.

Filters are cheap. Order them on amazon or Sewell online and save some money.

 

The 2002 Lexus All-Models Maintenance Interval Guide says to replace the engine air filter every 36 months or 48,000km (sooner if required).

A February 2009 study done for the US Department of Energy, by Oak Ridge National Laboratory (ORNL); Fuels, Engines and Emissions Research Center; National Transportation Research Center, states:

“The standard recommended service life for an air filter in light- and medium-duty applications, during normal driving conditions, is about 30,000 miles. It is common, however, for servicing to occur when the filter appears dirty. Engine air filters are designed to actually increase their efficiency by using this initial layer of dust as an added filter layer. Initial filter efficiency is usually approximately 98% but increases to more than 99% by the end of the service life of the filter. Therefore, changing an air filter before the useful service life is achieved can result in premature engine wear.”

"Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased."

"Closed-loop control in modern fuel injected vehicle applications is sophisticated enough to keep a clogged air filter from affecting the vehicle fuel economy. However for older, open-loop, carbureted vehicles, a clogged air filter can affect the fuel economy."

Source: http://www.osti.gov/bridge/product.b...asicsearch.jsp

 

Exactly what I was trying to state earlier. Thanks for the link.

 

StanVanDam Thank you for posting that interesting article.
Now I'll have to check the air filter and see how clean or dirty it is.

 

Stan - than ks for the informative post. I guess it makes sense that as filter gets full of particulates it will further trap more particles.

But even faced with rational objective data, I hate to say it but I am so OCD about this stuff, I change my filter every year - and typically vacuum it every 6 months to keep it as clean as possible. I just can't run a filter that looks as dirty as the one pictured. I do the same in the 3 HVAC units running in the house. Crazy? Maybe a little : )

 

I'm afraid I don't buy into their conclusions on the dirty filter. To state that an increase from 98% to more than 99% can result in "premature" engine wear seems to a bit illogical. While any increase in dirty air will likely increase engine wear, the amount of increased engine wear has to be quantified. That amount might be insignificant. Or, a measurable amount of engine wear might not be detected until 100,000 miles or more. Just stating that it is "premature" doesn't really tell me much.

Any added dust that increases the filter efficiency also adds to reducing the airflow. Any airflow reduction will reduce the engine power. But would that be quantified as a "significant" decrease?

So, according to this everyone should give their new airfilter a good dusting with some fine dirt before installing. Too bad they didn't define the micron size so we could buy some. Get my point?

 

Its hard to believe that your filters can be too clean. This being said, 10,000 miles seems a little premature but it all dependes on where you drive. That filter doesn't look bad at all. If it were me I'd blow it out and pop it back in and replace it along with whatever your next maint. item is if it bothers you.

Air filters can last a long, long time (15,000 miles or more depending on where you drive) without noticing any performance loss at all.

 

So I decided to go ahead and change the filter. The old one did not let a whole lot of light through, which I read is indicative of how dirty it really is. Disgusting as this may sound, I put my mouth to each one and took a pull, and there was a slight difference between the old and new one. (Sorry- had a childish- couldn't help myself kind of moment)

Once you see a new one next to the old one, You can't help but want to replace it. I feel better not trying to squeeze even another 5k out of this one. Let her breath!! I haven't driven the car yet, but will tonight and will see how it feels later, if there is any differences in driving characteristics.