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5 signs your air filter needs replacing

5 signs your air filter needs replacing

If we taped your mouth shut and made you run, you’d soon be desperate for air. We’d also probably earn ourselves a date with a judge. Don’t worry though, we’re not actually going to do that to you. 

We’re just highlighting how important the ability to breathe without restriction is in relation to performance. We need air, and so does your car. It needs to breathe, and if it can’t, your car is going to run like a bag of nails if it runs at all. 

The key part in your car’s respiratory system is the air filter. Without it, air and whatever detritus may be floating in it would be allowed deep into your engine.

The air filter stops them, making sure your cylinders only gulp down the good stuff. But how do you know if your air filter is having a hard life? Read on to find out. 

01 It’s dirty

First up, a visual clue that all might not be well. Is the filter dirty? Dirt means build-up, and build-up means reduced airflow. Not only that, it could be more than just dirt. There could be grease or oil on there, which will really soak into the filter’s fibres and as such, kill any airflow. There is no better solution to a dirty air filter than to bin it and fit a new one. 

02 It’s damaged

Has the air filter been improperly fitted and, in the process, crushed? Has it been bent out of shape before fitting? It might look all clean and nice, but the reality is that if the structure has been at all altered, it will impede the airflow. If your air filter is a shape different to what the manufacturer specified, don’t bother. 

03 The power is down

Does the car feel sluggish and lacking in the power department? Your mind might immediately go to a dark place – is it the engine, is it something deeply expensive? It may well just be the air filter.

If it can’t deliver the right amount of air into the engine, the engine is going to struggle to run. It’s that simple. Think of the taped-up mouth and running analogy from earlier.

And what’s more, this will mean…

04 It smells of fuel

If your engine isn’t getting enough air, it’s going to compensate by dumping a load more fuel into the engine. You’re going to smell that, so consider involuntarily getting high on super unleaded your warning of a bad air filter.

And it’ll mean bad things for the engine if you ignore it. More fuel that it should be getting can cause all kinds of running issues such as pinking, running hot and of course…

05 Poor economy

Yes, if your car suddenly starts costing more to run that you remember, it could well be down to the air filter. As detailed above, if it’s not getting enough air the engine will just guzzle more fuel.

This is why it’s a good idea to keep an eye on your car’s instant and average fuel economy. As the owner, you’ll notice any difference way before anyone else.