The air filter performs a simple task, you guessed it filters air.

The reason for this is that air contains lots of tiny (and not so tiny) particles of dirt that could run riot if they made their way into the engine.

Trapped dirt particles could get wedged between the piston and the bore causing premature wear and scoring to the bores and rings amongst other things.
The air filter is designed with a balance between flow and filtration

generally speaking the more filtering that is performed, the greater the restriction to airflow. The more airflow you allow, the better the performance of the engine.

A lot of the aftermarket filters use a concertina arrangement to expose a greater surface area and therefore permit greater flow of air. These can be fitted as an upgrade to any car but they are often noisier and I don’t think your average Volvo owner is willing to sacrifice comfort so I’m going to stick with stock for the purpose of the guide!

I picked up a Fram filter from my local auto factors for under £10. I’ve used a lot of Fram filters in the past and found them to be of good quality so had no hesitation in choosing one although I’m sure Volvo’s wouldn’t be too expensive either.

Fitting is a two minute job, here’s how :

Step 1

Locate the airbox on the nearside just in front of the suspension turret

Step 2

Release the 4 metal clips holding the box on, all are shown here. If they are stubborn then a flatblade screwdriver may be used but you should be able to do this with your fingers.

Step 3

The airbox will now lift up enough for you to slide out the filter (careful not to tug on the pipework at the other end too much)

Step 4

The air filter now simply pulls out of the airbox. I’ve shown pictures of mine against the new one (the bright yellow one), you can see it was very dirty indeed

Step 5

Now slide the new filter into the air box and press it down around the edges

Step 6

Do up the four clips and you’ve finished, easy!

 

Original posted in Volvo Owners Club Forum

The instructions in this tutorial will work in the following models / years:

– 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 and 2004 Volvo S40
– 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 and 2004 Volvo V40