Updated at: 27-07-2023 - By: micdot

It’s possible for you to get out of bed and start your automobile in the morning, but your diesel engine must first struggle to get going. Any driver could have encountered this predicament at some point in their lives.

Drivers know that weather conditions have a substantial impact on their vehicle’s condition and performance. This isn’t the first time I’ve had a problem with my automobile in the winter. As a result, we will now become well-versed in the world of diesel engines. This is where we will begin.

What Causes a Diesel to Be Hard to Start?

To put it mildly, that’s a tough scenario to find yourself in. Nobody would ever want their car not to start, of course. Even if you can’t get your car to start, you’ll need to consider all the likely causes. In the next section, we’ll go through all the possible causes of your diesel engine’s inability to start.

1. You Might Have Issues With Your Fuel Delivery

If you believe that your car has a problem with its fuel supply, you may always do a self-diagnostic. If the injector timing is correct, you should. Use a scan tool to see if this is the case.

The timing of your injectors will be determined by this. It’s also a good idea to look into whether or not the fuel contains any air. It’s highly likely that your engine may die shortly after starting if the fuel lines or the pump have any leaks. It’s possible that re-starting the engine will be tough as well. The fuel filters should also be inspected for blockage. Your fuel filters should be replaced every 20,000 to 40,000 miles. Checking and replacing fuel filters should be done on a regular basis. Consider the pump as an option as well. Always listen for a clicking sound when the engine is running. Turning the engine on and getting no clicking sounds could indicate a problem with the solenoid. It’s possible that your pump has to be replaced even if the engine starts with a click but no gasoline is delivered to the injector lines.

2. You Might Have Issues With Your Injectors

The pressure in a diesel injector is much higher than in a gasoline engine. But you needn’t be concerned. Over time, the pressure will decrease. Injector pressure must be regularly monitored to ensure it is neither too high nor too low. You should be aware that going to extremes is not a healthy thing. Your injectors may be filthy.

The white exhaust smoke you occasionally see coming from your exhaust is most likely coming from unclean injectors. In addition to a sluggish start, you may also notice a decrease of power. A leaking injector could be to blame if there is any black smoke coming out of your exhaust. You can check the resistance of your glow plugs or the temperature of the cylinders to see whether your injectors are bad.

3. You Might Have A Contaminated Fuel

Bacteria thrive in environments that are hot and humid. Diesel fuel is an ideal breeding ground for bacteria. Diesel attracts more bacteria than gasoline.

Warm temperatures encourage the growth of microorganisms such as bacteria. You need to make sure that your fuel is clean. If you see a green or black covering on the inside of your fuel tank, that’s bacteria building up. Sulfuric odor is another sign to check for. Getting rid of this drug as soon as possible is the recommended course of action. You must empty and thoroughly clean your fuel tank. You should also look for tainted parts in other areas of the vehicle. These pieces also need to be cleaned. Biocide can be added to your gasoline tank to prevent microorganisms from gaining access.

How Do You Start a Diesel Engine That Has Been Sitting?

To restart a diesel engine that has been sitting for some time, follow these simple instructions. Fill the tank with new petrol after draining the old one. Additionally, you’ll need to replace the gasoline filter. Remove the glow plugs and your engine will start more quickly. Fill the cylinders with MMO. Allow the cylinders to sit overnight after adding MMO. Crack the fuel lines in the injectors after that. The next day, you’ll need to drain the line that connects the injector union to the injector. You can do this by starting the engine and letting it run for a few minutes until the fuel dries up.

You should drain the cylinders of all the oil. By revving the starter in short bursts, you can avoid frying it. The fuel lines should then be tightened. Replace the glow plugs and your diesel engine should start right away after you’ve done this.

Is It Bad For a Diesel to Sit?

Even while diesel isn’t likely to harbor fungal or mold, it could. This is why regular use of diesel vehicles is necessary. Diesel has a lifespan of roughly 30 days if it goes wrong.

Heat is also required for the diesel engine. Once in a while, it should be driven around. Fuel must be warmed up before use. Despite the fact that many people claim to have had no issues with leaving their fuel in the tank, it is always better to be cautious than sorry.

How Long Can You Let a Diesel Engine Sit?

This is a question with several possible solutions. Many diesel engines have been sitting for months or even years without experiencing any major issues, thanks to careless drivers. Some drivers also advise against letting your diesel engine rest for long periods of time, as this can cause a variety of problems.

However, you can give it a whirl yourself. There’s no need to worry about your diesel engine while it’s being tested. Your diesel engine may have a threshold at which you can learn more about it.


A diesel engine might be difficult to start, to sum up. Cold weather is to blame on occasion.

It’s possible for germs to get into your fuel while it’s heated. Fungal and bacterial organisms thrive in diesel. If you plan on storing your diesel for a long period of time, you should think about this.