cobra101

got both filters out of my 06 e55 amg and realized I did not notice which way they were suppoed to be installed?

Either fins up and you can see the spaces like an accordion facing up

OR

Fins down and the flat (non-accordion style) side facing up?

Can damage occur if installed in the reverse position?

Thanks for any info.

Plutoe

The simplest way to learn yourself is to look at the old filters-----which side is dirty-----now you answered your own question!

Additionally, you have high velocity air traveling through the filter and you want maximum surface area to trap particles------which way would the filter go to meet that objective!!

cobra101

It was dirty all over. They fit so easily either way. I did find out it was fins (accoridan style) facing down with the flat side up.

Did not fix any of my issues but at least it's new.

Plutoe

Nice job---now you should get better gas mileage!!