One of the easiest jobs you can do on your BMW E46 3-Series is to replace the engine air filter. There are a whole host of benefits to replacing the engine air filter such as improved fuel efficiency, reduced emissions, and prolonged engine life.
Technically, the engine air filter replacement is done during BMW’s Inspection Service 2, which is done at every 60,000 miles. 60k miles is quite a long interval, but this is more of the recommended timeframe for newer vehicles. Since the E46 are now relatively aged, many E46 owners have increased the frequency of the air filter replacement to every 30,000 miles (or sooner.)
It also wouldn’t hurt to inspect your engine air filter between this replacement interval. Some people even replace their engine air filter at every oil change, but this is a bit overkill in my opinion. I would prefer to stick to changing the engine air filter at every 30k miles. This tutorial will apply to various BMW E46 models such as the 323i, 325i, 328i, and 330i coupes, sedans, wagons, and convertibles.
Tools & Materials
There are a couple of methods for replacing the engine air filter: one that is super easy, requires no tools, but requires some force; and the second that involves a bit more removal of components but safely accesses the air filter.
If you go with the latter, you’ll need some basic hand tools such as push-pin pliers (or alternatively a set of long nose pliers and a flat head screwdriver. You will of course also need the engine air filter itself.
Push Pin Pliers
GEARWRENCH 2 Pc. 30° & 80° Push Pin Plier Set
Engine Air Filter
The most common engine air filter that you’ll find for the E46 is the Mann Filter. This is an OE product, which is basically very close to OEM, if not the same. These generally cost around $12, while the BMW Genuine OEM air filter costs twice that. You can also get other aftermarket air filters for about the same price as the Mann Filter.
Mann (C25114/1): Amazon
BMW Genuine (Part #13-72-1-744-869): Amazon
Other Aftermarket Options: Fram Extra Guard CA9007 / ECOGARD XA5442
How to Change Engine Air Filter: BMW E46 3-Series
Quick and Easy Method
The first method is to simply undo the four clips that hold the top portion of the engine air filter housing in place. After you undo the (4 qty) clips on all sides, you can simply pull up on the top portion of the air filter housing and you can access the air filter. You can easily swap out the old one with a new air filter.
This is the easiest way to replace your engine air filter, but it does involve stressing some of the connected intake ducts. If you prefer not to stress these components (e.g. they may be brittle and break upon force) and/or you want to clean the inside of the air filter housing, continue reading for the second method of replacing the engine air filter.
Safer and More Accessible Method
You will be removing the front intake duct first. Remove the push pin clip on the air intake duct by using a push pin remover tool. You can also use a set of needle nose pliers to pull up on the push pin, and then pry up on the rest of the clip with a flat head screwdriver. Then remove the air intake duct.
Release the (5 qty) air filter housing clips on all sides of the air filter housing. With the clips released, you can remove the top air filter housing cover ensuring you pull it away from the existing plastic duct work. The air filter element can then be removed.
The new engine air filter goes right back in where the old one came. If you wish, you can vacuum up any dirty leaves, debris, or chunks of foam that may have broken off of the old engine air filter before installing the new air filter.
Replace everything back in the reverse order of removal and you are complete with your engine air filter replacement on your E46.
