How to start a diesel truck

Starting a diesel engine is very different from starting a gasoline engine. While a gas engine starts when the fuel is ignited by a spark plug, diesel engines rely on heat generated by compression in the combustion chamber. Sometimes, such as in cold weather, diesel fuel needs the help of an external heat source to reach the correct starting temperature. When starting a diesel engine, you have three main ways to do this: with an intake heater, with glow plugs, or with a block heater.

Method 1 of 3: Use an inlet heater

One way to start a diesel engine is to use intake air heaters, which are located in the intake manifold and heat the air entering the engine's cylinders. Powered directly from the vehicle's battery, an intake heater is a great way to quickly raise the air temperature in the combustion chamber to where it needs to be, allowing the diesel engine to start when needed, with the added benefit of being away with white, gray or black smoke often generated when starting a cold engine.

Step 1: Turn the key. Turn the ignition key to start the diesel engine starting process.

Glow plugs are still used in this starting method, so you need to wait for them to warm up before the car can start properly.

The intake air heater is designed to quickly heat the air entering the combustion chambers to normal operating temperature.

Step 2: Turn the key again and start the engine.. The air intake heaters use the power generated by the battery to start heating the element installed in the air intake pipe.

As the vehicle pulls away and the air passes through the heating elements, it enters the combustion chambers warmer than without the aid of the air intake heaters.

This helps to reduce or eliminate the white or gray smoke normally produced when starting a diesel engine. This condition occurs when diesel fuel passes through the combustion process unburned and is the result of a too cold combustion chamber causing lower compression.

Method 2 of 3: Using Glow Plugs

The most common method of starting a diesel engine is by using glow plugs. Like the air intake, glow plugs are powered by the vehicle's battery. This preheating process brings the air in the combustion chamber to a temperature conducive to cold starts.

Step 1: Turn the key. A "Please wait to start" indicator should appear on the dashboard.

Glow plugs can heat up to 15 seconds or longer in cold weather.

When the glow plugs reach their normal operating temperature, the "Wait to start" light should turn off.

Step 2: start the engine. After the "Wait to start" indicator goes out, try to start the engine.

Do not try to start the car for more than 30 seconds. If the car starts, release the key. Otherwise, turn the key to the off position.

Step 3: Heat the Glow Plugs Again. Turn the key until the "Waiting to start" indicator lights up again.

Wait until the indicator goes out, indicating that the glow plugs are sufficiently heated. This may take up to 15 seconds or more, depending on the temperature.

Step 4: Try to start the car again.. After the "Wait to start" indicator goes off, try to start the car again.

Turn the key to the start position, cranking the engine for no more than 30 seconds. If the car won't start, turn the key to the off position and consider other options, such as using a heater.

Method 3 of 3: Using the Block Heater

If both the glow plugs and the air intake heater cannot heat the air in the combustion chamber enough to start, you should consider using a block heater. Just as glow plugs heat the air in the combustion chamber and the air intake heater heats the air entering the intake manifold, the cylinder block heater heats the engine block. This makes it easier to start the diesel engine in cold weather.

Necessary materials

• Power socket

Step 1: Connect block heater. This step requires you to pull the block heater plug out of the front of the car.

Some models have a port through which a plug can be inserted; otherwise, place it through the front grille. Use an extension cord to connect your vehicle to an available outlet.

• A warning: Most block heater plugs have three prongs and require an appropriate extension cord connection.

Step 2: Leave the block heater plugged in.. Let the loader stand connected to the mains for at least two hours before starting.

The block heater heats the coolant in the cylinder block to help warm the entire engine.

Step 3: start the engine. Once the coolant and engine are warm enough, attempt to start the vehicle as described above.

This includes waiting for the "Please Wait to Start" light to turn off, which can take up to 15 seconds or longer, depending on the temperature in the combustion chamber. After the "Wait to start" indicator goes out, try cranking the engine for no more than 30 seconds.

If the engine still won't start, seek help from an experienced diesel mechanic as your problem is most likely related to something else.

Starting a diesel engine can sometimes be difficult, especially in cold weather. Luckily, you have a few options when it comes to getting the combustion chamber temperature high enough to start your car. If you have trouble starting your diesel truck or have general questions, see your mechanic to see what you can do to make starting your diesel truck easier.