Fuel filter MAZDA 3 Saloon (BP)

Ah, hunting for the diesel filter on a 2019 Mazda 3 1.8 diesel, are we? It’s almost like Mazda hid it as a test: “If you can find this, you’re worthy to own the car!” Spoiler alert—it’s sneakier than your dog when biscuits come out.

Here’s the inside scoop: On the 2019 Mazda 3 1.8 SKYACTIV-D diesel, the fuel filter is located in the engine bay, not in the tank or rear like you’d find in some other models. If you pop the bonnet and eyeball the bit between the engine and battery (usually tucked near the firewall or not far from the battery area), you should spot a cylindrical filter inside a black plastic housing. It’s held with a bracket and has a couple of fuel lines coming from it—don’t worry, it’s not a trap, just good ol’ diesel engineering.

For most Mazda SKYACTIV-D 1.8s, you’ll need to:
- Remove the battery (don’t drop it on your toes, it’s heavier than it looks!).
- Unclip two fuel lines (masking tape is your friend for labeling, so you don’t swap them by accident and end up inventing a new Mazda feature).
- Undo the bracket holding the filter.
- The old filter will probably dribble diesel all over your hand, so wear gloves unless you fancy smelling like a petrol station for a week.

Top tip: fill the new filter with diesel before fitting, so you don’t get a marathon cranking session trying to prime the system. That’s the secret handshake for fast starts after a filter change.

So, in summary: engine bay, near the battery, sitting in a bracket. Not under the rear seat, not buried in the tank—Mazda actually made it accessible-ish this time. Now you can go out and wrestle with it, and if anyone asks why you’re elbow-deep in your engine bay, just wink and say you’re fighting the diesel filter boss level. Good luck!