No arrow on air filter, which side up?
 

I purchased an air filter but there is no arrow on it and can't tell which side is up?
https://cimg2.ibsrv.net/gimg/www.clu...605e6c3f29.jpg
Attached a picture.

Previous one mechanic installed, it had an arrow but I believe was facing down which seems to be incorrect.

I've seen them marked both ways. Some of them would have arrow showing direction of the airflow (it would have word "AIRFLOW" on it), in this case arrow should be pointing down. Another option is with the arrow pointing up, it would say "THIS WAY UP". If your filter doesn't have any markings it is probably doesn't have any particular direction and can be installed either way up.

Sounds like a budget air filter. OEM or reputable brands always have an arrow indicating airflow.

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Ones with arrows usually have one side with a different media that will catch larger particles, while the other does more fine filtering. If a filter is not marked, it probably has the same filtering all the way through. There are some designs that have a direction because of a lip that fits on the filter housing one way only.

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