Does Dirty Diesel Damage Your Engine?

April 20, 2021

Thanks to the quality and longevity of the High-Pressure Common Rail (HPCR) diesel engine now available in newer vehicle models, diesel cars are becoming more and more popular in Australia. These engines provide better fuel economy, higher torque, lower maintenance, and a longer lifespan – so long as they are kept healthy and maintained well!  

The biggest threat HPCR diesel engine owners now face is that of dirty diesel. The fuel-injected nature of modern diesel engines makes them highly susceptible to the effects of dirty, or contaminated, diesel fuel. What is dirty diesel, how does it get contaminated, and how can you prevent it from finding its way into your system? Read on to find out!  

Does Dirty Diesel Damage Your Engine?  

What is Dirty Diesel? 

Dirty diesel is diesel fuel that has been contaminated by external materials. Usually, this is water – which does not blend with diesel – or particulates, which can be made up of a variety of materials that the fuel had been in contact with during its journey to your vehicle.  

What Causes Dirty Diesel?  

Diesel fuel passes through many forms of storage after the refinement process, any of which could cause contamination. Corroded or rusted surfaces, poor storage management, and even the truck tanker journey can cause unwanted particulates to enter and contaminate the diesel. 

Although these particulates are incredibly small, small enough that the naked human eye cannot see them, the areas within your engine through which the fuel passes are just as small! Important performance parts within your engine can quickly break down because of the corrosive effects of the granular particulates contaminating your fuel, such as the HPCR injector, ball seat valves, and even pumps. Particulates as small as 1 micron in size (a single human hair is around 70 microns, for comparison) can make some engine parts look as though they have been sandblasted!  

How to Know if Your Engine Has Been Affected by Dirty Diesel 

Check Engine Light 

Do not underestimate the power of this little light. By ignoring it, you risk that corrosive fuel is quickly wearing down your engine, part by part! Continuous operation under these conditions can lead to total engine failure.  

Clogged Fuel Filters 

The higher quality of your fuel filter, the better its chances of catching all those nasty little particulates – which is what you want, but which is exactly why clogged fuel filters should be changed regularly!  

Fuel Pump Failure 

If your fuel filters clog up often, your fuel pump may be at risk of failure. A failing fuel pump will not be able to deliver the correct amount of fuel and can interrupt the workings of the engine, usually most noticeably when accelerating.  

The following signs may be a sign of a failing fuel pump: 

  • Loss of power when accelerating 
  • Loss of power when driving up slopes 
  • Loss of power when towing 
  • Jerks or sputters when travelling at high speeds 
  • Engine refusing to fire.  

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Injector Failure  

Injectors do not fail immediately and can remain operable for some time before giving way to catastrophic engine injector failure. However, while failing, they can cause your engine’s performance and efficiency to decline. Symptoms of failing injectors include: 

  • Poor idling 
  • Poor engine start 
  • Smoke 
  • Increased fuel consumption 
  • Reduced engine power and RPM 
  • Noise 

How to Prevent Dirty Diesel from Entering Your Engine 

The simplest but most effective solution? Only purchase quality diesel fuel for your engine. Australia has strict fuel quality standards and aims to ensure that the fuel used is not only safe for the environment but also allows vehicles to operate optimally and efficiently. However, it is possible to encounter lower quality fuel in rural areas.  

Additionally, it is crucial to properly maintain your engine and its components – especially those involved with fuel supply and delivery.  

You should avoid storing diesel for long periods of time and then using it, as the quality of fuel can decline over time. Also, try to avoid letting your fuel tank get too empty, as this can increase and unbalance your particulate-to-fuel ratio, as well as cause unwanted water and fuel mixing.  

Need Help from Diesel Performance Experts? 

Just Autos are the experts for all things diesel! We know diesel engines and how to properly care for them – as well as how to enhance their performance! If you are looking to improve your engine, get in touch with a friendly member of our team today, or head to our workshop in Nambour.  

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