What Are The Most Common Diesel Engine Problems?

Do you find yourself occasionally experiencing engine issues while traveling or on road trips? While diesel engines are more fuel-efficient than standard gas vehicles, that does not mean they are immune to numerous problems throughout their lives. Although regular wear and tear are part of an engine’s life cycle, several common diesel engine issues may occur.

If they are not appropriately maintained, diesel engines can develop a multitude of different problems, either internal or external. It is unlikely that your diesel engine will never break down or underperform — however, if this occurs, you will want to get back on the road as soon as possible. So, knowing how to recognize some of the most frequent problems can assist with that.

As a car or truck owner, you may already know the benefits that come with owning a diesel vehicle, but it’s also essential to understand some of the unique issues that can arise. With that, we have a guide to help you understand common diesel engine problems so you will be aware if your car’s diesel engine encounters an issue.

Problem #1. Black Exhaust 

If you travel behind a diesel-powered car or truck daily, you may have noticed black exhaust as one of the typical indicators that appear to signal a problem. The presence of black exhaust fumes is frequently the result of an imbalance in the engine’s air-to-fuel ratio. When there is too much gasoline and not enough air, they can build up a black and foul-smelling exhaust. 

Aside from that, an injector pump, a defective air filter, or an EGR valve issue can disrupt the air-fuel ratio. It cannot be easy to point out without a more thorough examination of the engine. As a result, if you notice black exhaust coming from your vehicle or machinery, you should always seek the advice of a professional diesel mechanic.

Problem #2. Engine Oil Oxidation

When a diesel engine vehicle sits for a long time or is operated only on occasion, the oil can become contaminated. This tends to happen when air gets into the oil and forms bubbles that obstruct lubrication. Beyond that, because the oil thins out due to the air bubbles, they may end up causing rust and friction in moving components.

On that point, oxidized oil results in increased viscosity and quick degradation, as well as deposits and sludge. People feel the oil is unclean and has outlived its usefulness because of the sludge. However, nothing has changed. Chemistry is the only thing that is changing. With that, you need to replace the oil, but ensure it’s a new one that can last longer regardless of heat and oxygen.

Problem #3. Engine Overheating

Overheating is perhaps the biggest significant problem with diesel engines. Overheating often appears when you are pushing the engine excessively hard. It can also develop in other issues such as shattering or distorting of cylinder heads and damage to the bearings and crankshaft. The following are some of the causes of diesel engine overheating:

  • Broken thermostat – A thermostat helps protect the engine from overheating. It features a valve that opens and closes to monitor engine temperatures. It can’t detect when the engine is overheating and, as a result, can’t activate cooling responses if it’s broken.
  • Coolant leaks – Leaking coolant is indicated by a large number of bubbles and low coolant levels.
  • Clogged diesel injectors – Leaks and blockages in your fuel injector can cause overheating. When the injection system fails to discharge fuel as it should, the engine needs to work extra hard, causing it to overheat.
  • Defective cooling fan – A malfunctioning cooling fan can end up causing the engine to overheat and result in electrical difficulties.

Problem #4. Wrong Weight Viscosity

The improper weight viscosity of engine lubrication is often the cause of hard starting. Diesel lubricants have a substantially higher viscosity than gasoline, and many individuals misunderstand the viscosity weight when changing the oil.

In some cases, they may also utilize a single-weight engine oil during hot weather and then fail to convert to a multi-viscosity oil when the temperature cools. For you to avoid potentially damaging the engine, it’s preferable to use multi-viscosity oil all year.

Problem #5. Slow Acceleration

While diesel vehicles aren’t famous for their rapid acceleration, slow acceleration appears to indicate an issue. A clogged catalytic converter might be the cause of your diesel vehicle’s inability to accelerate as quickly as it once performed. It’s also possible that the fuel filter on your diesel engine needs a replacement. If your diesel vehicle is slow to accelerate and not overheating, it could be a transmission problem. 

Problem #6. Higher Compression Ratio

The compression ratio of a typical diesel engine is 20:1. With that ratio, it makes the diesel engine becomes more powerful, ultra-efficient, and torquey. However, this situation has the potential to cause massive complications in the long run. For example, it may result in the engine knocking more frequently than usual, resulting in fuel-burning patterns. Compression levels that are too high can also cause problems with the fuel injectors.

How Mach1 Motorsports Can Assist You

It’s inevitable that at some time in your life, you’re going to need repairs for your diesel vehicle, or at least a place to take your vehicle when problems do arise. Our customers at Mach1 Motorsports are our top priority. We will keep your on- or off-road vehicle running like new and ensure your repairs are done correctly the first time.

We promise to be honest, and we won’t sell you something you don’t need. We want you to tell your friends and family about us and come back whenever you need parts, service, and diagnostics from the latest equipment.

Our focus is on providing high-quality service and customer satisfaction, meeting and exceeding your expectations. Contact us today to learn what we can do to help while you are out on the highway, the trails, mudding, climbing, or just enjoying the fresh air while on a trail ride.

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