How To Diagnose Your Diesel Engine

Automotive Blog

Diesel engines are reknowned for their reliability, durability and fuel efficiency. If you own a diesel vehicle, you might be a bit confused when it develops problems. This article explains how to diagnose the various diesel engine problems. 

Low Power

A decrease in engine power can cause panic. For example, your vehicle could be unable to overtake or climb a small hill. Below are reasons why a diesel engine could be underpowered: 

  • A clogged air filter will prevent fuel in the combustion chamber from burning. Consequently, the engine will lose power.
  • Problems along the fuel line, including damaged injectors, dysfunctional filters and fuel pumps, could also be the reason why the vehicle is losing power.
  • The throttle linkage is a cable that controls the mass airflow sensor (MAF). If it is damaged, the MAF could send the wrong signals to the ECU, leading to an imbalance in the air-fuel mixture. As a result, the vehicle will lose power.
  • A glow plug is a component that heats the fuel and air in the combustion chamber. If it is worn out, the engine could lose power, misfire or have trouble starting. 

Overheating Engine

Once the engine begins to overheat, the temperature gauge will rise continuously or sporadically, depending on your driving style. An overheating engine could suffer severe damage that could compel you to replace the entire engine. Therefore, if this happens, stop the engineand call in professional help. 

Nonetheless, there are many reasons why a diesel engine could overheat. Some issues are interconnected. For example, if the vehicle has low power, you may be forced to drive it at high revs, thus overworking the engine. In this case, the engine will overheat. Other culprits include a damaged water pump, leakages in the cooling system, faulty fans or a damaged thermostat. 

Oil Oxidation

Oil oxidation occurs when the engine oil reacts with oxygen, thus losing its properties. Once the oil oxidises, it increases its viscosity. In severe cases, it will form sludge. Oxidised oil degrades before its recommended mileage. Proper engine prevents oil oxidation. Besides, you should not leave the engine idle for too long. Additionally, use high-quality oils that have a high oxidation resistance.  

Contaminated Fuel

Diesel could get contaminated from the source or inside the vehicle. For example, worn-out seals could let in dust and other contaminants. If the car has contaminated fuel, it could jerk at high speeds, lose power, produce white smoke or increase fuel consumption. If your vehicle suffers fuel contamination, take it to a professional to determine the cause of the contamination. In most cases, they will drain the fuel after repairs to ensure you do not drive with contaminated fuel. 

Contact a local auto shop if you need help with diesel diagnostics.


17 November 2021

My Love For Fast Cars

Ever since I was a little boy playing with my toy cars, I have had a need for speed. Now that I am an adult, I enjoy both watching car racing and taking part in amateur racing events. My automotive blog shares ways you can make your own car faster and more responsive. I want to share my thoughts on tyre choices, mechanical modifications and body style changes which all alter the way your car performs. If you have an interest in amateur car racing, you'll find posts about that here. My blog posts get keep your engine racing too!