Troubleshooting Some Common Diesel Engine Problems

A diesel engine is known to be rough and rugged and able to handle larger towing loads; it's often called the workhorse of engines for that very reason. However, it can still break down and sputter while on the road, or outright refuse to start, and especially if you keep the vehicle overloaded or don't maintain the engine as you should. Note a few common diesel engine problems you might encounter with your vehicle so you know where to start looking when it begins to act up, and what the engine might need by way of repairs.

Engine starts but won't idle

If the engine stalls when you're idling, this could be caused by a faulty timer. This piece controls the timing of the pistons as they move through the engine chambers; if the timer is malfunctioning, it may allow the pistons to stop moving or to move too slowly to keep the engine idling.

A tank of contaminated fuel can also be the culprit; some vehicle owners mix gasoline with diesel or use additives meant for standard petrol in their engine, mistakenly thinking this will allow their engine to run cleaner or be more fuel efficient. That contaminated fuel may move too slow to make its way to the engine when you're idling, also allowing it to stall.

Engine lacks power

Your first and most obvious fix to this issue is to lighten the load of the vehicle; while a diesel engine is strong, if the vehicle is overloaded, it won't be able to accelerate or climb hills so easily. However, there could also be restricted fuel intake from the fuel injectors, or low compression that is not causing the fuel to heat as it should. Cleaning the fuel injectors can often address this problem.

Smoke from the engine or tailpipe

If the smoke is black, this often means the engine is overloaded and hauling too much weight. If there is not enough air intake into the engine, this can also cause the fuel to burn and black smoke to form; change the air filter as needed.

If a clutch is not disengaged, this can cause the transmission to overheat and smoke. Check the clutch and gears of the transmission to note if any are worn down and need replacing.

Contaminated or old fuel may also smoke as those contaminants burn away in the heat of the engine. Degraded fuel that is very old may cause white smoke from the tailpipe when it burns, so drain the fuel tank and fill it with fresh fuel to note if this corrects the problem.