While today’s diagnostic tools and advanced engine electronics have made it easier to pinpoint drive-ability problems in diesel engines, it doesn’t mean that all problems are solved so easily
Owners often think that because diesel engines are now computer-controlled, the technician should be able to hook up a scan tool and immediately see what is going on but that is not always the case, some problems may be tougher than you think
Some of the most common problems associated with a diesel engine are:
Oxidised Oil. This can occur when a vehicle sits in one place too long, operate infrequently – Oxidised oil means that air gets into the oil, and creates bubbles that can interfere with proper lubrication, which can result in a faltering or even damaged engine. Even though the oil isn’t technically dirty, it needs to be changed as soon as possible after this idle period.
Humidity Reactions. Water attacks additives and increases oxidation. It can also interfere with the lubrication process, which can lead to a severely damaged machine.
Black Exhaust. The exhaust is generally a result of an imbalanced air to fuel ratio, leaning on the side of too much fuel and not enough air. A faulty injector, injector pump, air filter, EGR valve, or even turbocharger could be the root of the problem.
Hard Starting. If your vehicle has an extremely difficult time starting, cranks more than normal, or won’t start at all, it’s important to get things checked out as soon as possible.
Lack of Power. This symptom could be caused by dirty fuel filters, loose throttle linkage, excessive lubrication, and issues with the fuel injectors amongst others
Defective Glow Plug. Diesel engines don’t have spark plugs to ignite the fuel-air mixture in their cylinders like petrol-powered cars. They rely on glow plugs to ignite the mixtures through a high-resistance heating element. When the glow plug goes bad, it makes it nearly impossible for the engine to start, particularly in cold weather.
Contaminated Fuel. Because diesel is much more viscous than gasoline, it can become more easily contaminated. The four most common, and equally dangerous, fuel contaminants include glycol, dilution, soot, and water.
Noise. Diesel engines can be significantly noisier than the petrol engine vehicles, but excessive noise can also be a sign of something wrong. If you notice inconsistent noise or distinct knocking in the engine, it could be a sign of a problem with the fuel injectors, which can affect the compression balance and reduce performance to start with.