Rising Fuel Costs?
Here Are 5 Common Causes and Easy Fixes 

Why Is My Car Eating So Much Petrol Lately? 5 Common Culprits

If you've been filling up more often than usual, you're not imagining it. Fuel consumption creeping upward over time is one of the most common and most frustrating signs that something in your car needs attention. The good news is that most causes are simple, inexpensive to fix, and don't require a trip to a full workshop overhaul.

Here are five of the most common reasons your car might be drinking more petrol than it should and where to start fixing it.

1. Underinflated Tyres

It sounds too simple to matter, but tyre pressure has a direct impact on fuel efficiency. When your tyres are underinflated, more of the tyre surface touches the road, increasing rolling resistance. Your engine then has to work harder just to keep the car moving at the same speed, burning extra fuel in the process.

Quick fix: Check your tyre pressure monthly against the recommended PSI listed on your door frame or fuel cap, it takes two minutes at any petrol station.

2. Old or Worn Spark Plugs

Spark plugs are responsible for igniting the air-fuel mixture in your engine's combustion chamber. Over time, they wear down, develop carbon deposits, or start misfiring. When that happens, combustion becomes incomplete and inefficient, meaning your engine burns more fuel to produce the same amount of power.

Quick fix: Most spark plugs need replacing every 30,000 - 100,000 km depending on the type (copper, platinum, or iridium). If your car feels like it's struggling to start or idles roughly, it may be time to check them.

3. Carbon Buildup on Fuel Injectors

This is one of the most overlooked causes and often the most impactful. Every time your engine burns fuel, tiny amounts of unburned residue are left behind, gradually hardening into carbon deposits on your fuel injectors and intake valves. Once clogged, injectors can't deliver a clean, even spray of fuel, which disrupts combustion and forces your engine to work harder for the same output.

Quick fix: This is where a fuel system treatment can help more on that below.

4. A Clogged Air Filter

Your engine needs the right balance of air and fuel to combust efficiently. A dirty or clogged air filter restricts airflow, throwing that balance off and forcing the engine to compensate by using more fuel.

Quick fix: Air filters are cheap and easy to replace, most cars need a new one every 15,000 - 30,000 km, or sooner if you drive in dusty conditions often.

5. Poor Driving Habits

Sometimes the issue isn't mechanical at all. Frequent hard acceleration, excessive idling, and short stop-start city trips all increase fuel consumption significantly compared to steady, smooth driving.

Quick fix: Where possible, ease off the accelerator, avoid unnecessary idling, and try to maintain a consistent speed on longer drives.

The Easiest First Step: Tackling Carbon Buildup with BioFuel

Out of all five culprits, carbon buildup on your fuel injectors is often the cheapest and fastest issue to address and it's usually the one drivers overlook the longest, since the symptoms (sluggish acceleration, rough idling, high fuel use) get blamed on "the car just getting old."

BioFuel is a plant-refined bio-oil formula designed to loosen and clear carbon deposits from your fuel system, without the harsh chemical stripping used in many traditional injector cleaners. As it moves through the fuel system, it helps break down the resin-like structure of carbon deposits, allowing them to burn off cleanly or pass safely out through the exhaust without damaging seals or internal components.

It comes in two formulations, petrol and diesel, so you can match it to your vehicle's fuel type. Compared to a full workshop injector cleaning service, it's one of the lowest-cost, lowest-effort ways to address one of the biggest silent drains on your fuel economy, simply pour it into your tank at your next refuel.

Before you assume your car is just "getting old," it's worth ruling out carbon buildup first. It's often the easiest problem on this list to fix, and one bottle could be the difference between constant top-ups and getting your old mileage back.