Are you worried about your diesel pickup truck blowing white smoke? This could be the result of several possible issues– each indicative of problems with specific components or systems.

It is important to know that your diesel truck can emit either black, white, or blue smoke from the exhaust. The color of the smoke can tell a lot about the performance and running condition of your vehicle.

The only way to get an accurate diagnosis is via a detailed examination by a professional diesel truck technician.

So, regardless of whether you drive a domestic or commercial grade diesel pickup, it is best to get a professional assessment of the condition of your vehicle before you run into any serious trouble down the road … even if those roads are in the beautiful state of Idaho!

5 Reasons Why Your Diesel Truck is Blowing White Smoke

Diesel engine fuel, as mentioned above, can blow different colored (black, blue, or white) smoke from the exhaust. However, if your diesel pickup truck is specifically blowing white smoke, there could be a few different reasons why. These include the ones listed below.

White Smoke While Starting the Engine

A common condition for white smoke blowing from your vehicle’s exhaust is condensation. When the temperature outside is low or if the conditions are damp, condensation can manifest itself inside the exhaust pipes, the mufflers, or the converter. This can then produce white smoke when you start your vehicle.

If it continues while driving, even for a short period, it could be because the tiny fuel droplets freeze while leaving the heated exhaust. This can then lead to the emission of white smoke even while driving. Once your engine reaches the normal temperature, the white smoke should disappear.

Burning Transmission Fluid

If the vacuum modulators (located at the side of the transmission case) has a faulty diaphragm valve, then this can lead to the transmission fluid entering the intake system via the vacuum hose-line.

If this happens, an early warning sign will be issues with shifting in automatic transmission system. You will also find that the transmission fluid consumption goes up.

Burning transmission fluid, like unburned fuel, is also white and will leave a sharp pungent odor.

Unburned Fuel

Another common reason for your exhaust to blow white smoke is because of unburned fuel. A faulty engine timing.

Low compression in the engine cylinders can lead to incomplete engine combustion. What this means is that worn rings and burnt valves can allow the flow of raw fuel.

Dirty nozzles in the diesel injectors can impact the spray pattern which can then lead to raw fuel passing through the exhaust. The unburned fuel passing through will have a strong odor.

Leak in the Coolant System

If there is a leak in the coolant system, then the coolant can pass through the combustion chamber from a cracked block or head, or a blown head gasket. It could even be from a bad injector sleeve or a leaking intercooler.

A damaged head gasket, close to the exhaust port side, can lead to the liquid coolant entering the cylinders and passing via the exhaust. The same can happen due to a cracked engine block or cylinder head.

A strong indicator that this is due to a leak in the coolant system is that the passing vapor will not have an acrid smell, as in the case with unburned fuel – instead it will probably smell kind of sweet.

On top of this, if you find the radiator or reservoir coolant levels constantly falling, then it could again indicate a blown head gasket, or a cracked block or head.

Contaminated Fuel

One of the most common contaminants of fuel is water. This contaminated fuel, often pumped through the fuel delivery system, upon burning, can generate a steam effect inside the cylinder. So, if your vehicle has contaminated fuel, then this could also be the cause for white smoke blowing through the exhaust.

Reliable Diesel Repair Service!

Is your diesel pickup truck blowing white smoke? Or are you facing any other kind of trouble with your diesel pickup truck? We can help.

We guarantee 24-month, 24,000 mile warranty. So visit us at Gem State Diesel or call us at 208-288-5555 to set up an appointment today!