Air Filter Change Intervals

[maxnix]

Before joing this board, I would change my air filters for the engine about 15K - 20K miles on my none Infiniti vehicles. I don't know if the Infiniti Q45 filters are more efficient, but Q45tech is correct in that they are degraded at 12K miles.

I recently changed my wife's FY33 2000 Q45 filter at 17K (assuming the dealer did it at 30K service, don't know since Montclair Infiniti service manager never answered email requesting detail of the 30K service), and it looked like is was driven on freshly laid asphalt roads all it's life. My second one on my G50 1995 Q45t at 14K miles (traveling too much) was not as bad but degraded nonetheless. The area downstream in the MAF looked pristine like it came off the showroom floor. A wipe with a paper towel revealed NO deposits. These OEM filters work! At $12 from Joe, it is a no brainer. Now, I am worried about what my lungs must be like.

His admonition to change the fuel filters at 12K is well taken too for longer fuel pump life. The math says between 600-800 gallons have passed through it. Again, at $10 from Joe, and a few busted knuckles, cheap. Now to get that triple beam gram scale to measure before and after use weight to determine contaminants caught.

Just surprised I haven't seen more posts on this, but perhaps I am just restating the obvious. Dennis is right-on again.

[szh]

The Infiniti recommended interval on the M45 is 30k miles, same as the Q45, I believe (I no longer have the service manual for the 95 Q45 - gave it to the new owner of my car and deleted from my computer). Sounds like it would be good to do them sooner on the M4 too!

Hmmm ...

Z

[Q45tech]

"The Infiniti recommended interval on the M45 is 30k miles" so that the engine won't fail for 100k but who cares there after we sure don't, we want to sell you a new car!

Don't assume that any of these minimal recommendations are designed to help you make 200,000 miles.

Doesn't the manual say in tiny fine print at bottom "in dusty or adverse [normal] conditions" to change every year or 12,000 miles

[szh]

Doesn't the manual say in tiny fine print at bottom "in dusty or adverse [normal] conditions" to change every year or 12,000 miles

Does not give the miles or time, but it sure does have words to that effect. The manual (service manual) says "If operating mainly in dusty conditions, more frequent maintenance may be required."

I guess I have always assumed that normal driving (combined 75-80% highway and 20-25% city) around the Bay Area is not considered "mainly in dusty conditions"! My early read of that fine-print caveat was that it was intended for folks who lived off the beaten path, down non-paved roads, etc.!

But, now I will follow more stringent guidelines ... as recommended by you here!

Z

[greg_atlanta]

I change mine once a year after the pollen goes away in late spring.

[Q45tech]

In desert storm they had to clean the ultra expensive air filters every night, so annually [15k] should be often enough in most places in US. Depends on how soon you want too lose compression [upper ring wear].

[AZhitman]

I've changed mine ever 6 months faithfully. No sense tempting fate for $14 a year.

[Q45tech]

Upper/top ring wear is purely a function of injested dirt and it can only come from air filter .........as everything else is closed loop even the egr carbon [is soft] not hard like silicon [sand particles].

[Q45tech]

Upper/top ring wear is purely a function of injested dirt and it can only come from air filter .........as everything else is closed loop even the egr carbon [is soft] not hard like silicon [sand particles].

40 cubic feet of air per minute [assume 25% VE] at 60 mph cruise x 200,000 minutes; 8 million cubic feet of air contains how much dirt?