What You need To Do In Changing Your Car’s Air Filters


On most modern vehicles, the environment filter is under the hood inside a rectangular cold air collector box that’s located up near the front of the engine compartment. (Other vehicles, including those that have carburetors, have big round metal air cleaners that happen to be hard to miss.)

The air cleaner has a large air inlet duct (also referred to as the air intake hose) connected to it. Loosen the hose clamp that seals it to the box, and then undo all thescrews and clamps, or wing nuts that retain the lid from the box in place. Put the fasteners you removed somewhere safe so that they don’t roll off into oblivion. Open the lid of your box and . . . voila! . . . you ought to find the air filter inside (as shown here). Lift out the old filter (it isn’t fastened down) and take a look at it.

The cold air collector box houses the air filter.

The cold air collector box houses the air filter.

Some older vehicles have permanent air filters, plus some off-road vehicles have more-complex filters with dry and wet elements. Clean and replace these based on the instructions within your owner’s manual.

To figure out whether your air filter should be replaced, just hold it to the sun or to a powerful light. Can you see the light streaming through it? If not, try dropping it lightly, bottom side down, on a hard surface. Doing so should jar some dirt loose. If the filter is still too dirty to see through after you’ve dropped it once or twice and it looks as though it just needs a bit of cleaning, you can attempt to clean it. You will need a new one in the event that doesn’t work.

To clean a pleated air filter use either an air hose to blow the dirt off (not through) it or possibly a vacuum to suck it all out. For both methods, handle the filter gently to avoid crushing the pleats. Keep the nozzle of the air hose or vacuum cleaner several inches outside the filter – don’t jam it up against it. And if you’re using compressed air, do it out of the vehicle in order to avoid blowing the dirt around under the hood.

If the interior of the box is fouled with dust or sand, before you clean the box paste some duct tape over the open end of the air intake hose so that the dirt can’t be in. Then either use the compressed air hose to blow the dirt out of the box or the cleaner to suck it out.

When the cleaned filter – or maybe the new one – is in place, put the lid back about the box and replace everything that held it on. Then, eliminate the duct tape from the open end of your air intake hose and employ the hose clamp to reattach it to the box. Done!