Yes, bad diesel fuel is a primary cause of injector failure, leading to issues like clogging, corrosion, and excessive wear from contaminants, water, or poor lubricity, which damages the injectors' precise internal components and spray patterns, ultimately causing poor performance, smoke, and engine damage.
Common Causes of Diesel Fuel Injector Failure
With that in mind, let's take a look at the most common symptoms that might indicate that a diesel injector is failing.
Spotting the Problem: Symptoms of bad diesel or contaminated fuel include poor engine performance, rough idling, increased exhaust smoke, and a foul smell from the fuel. The engine might also struggle to start or run unevenly.
Common causes of injector failure
However, they're still susceptible to issues. While many things can cause breakdowns, the most likely cause of premature failure is fuel contamination.
Important performance parts within your engine can quickly break down because of the corrosive effects of the granular particulates contaminating your fuel, such as the HPCR injector, ball seat valves, and even pumps.
You've probably wondered how long your car's fuel injectors can last, especially when you start noticing slight changes in your engine's performance. Typically, they should serve you well for 50,000 to 100,000 miles, depending on whether you drive a gasoline or diesel engine.
The following are 12 signs of a bad diesel engine:
Fuel injectors work as a set, and replacing just one can lead to imbalances in your engine's performance. When one injector fails, it often indicates that the others are nearing the end of their lifespans too. Replacing all injectors at once ensures consistent fuel delivery and optimal engine performance.
The symptoms of 'Black Death' are typically gradual, starting with a loss of power, rough idling, and decreased fuel efficiency. As the condition worsens, the engine may begin to emit black smoke from the exhaust, experience misfires, and even stall while driving.
Can you drive with a faulty diesel injector? While the truck might still move, it is highly not recommended. Driving with a faulty injector leads to poor performance, terrible fuel economy, and increased emissions that can damage the DPF system.
Direct injection and common-rail diesel injectors
The cost of replacing fuel injectors in diesel engines can vary significantly depending on the vehicle model and injector design. Diesel injectors typically range from £150 to £250 each, with prices exceeding £300 in some high-performance or specialised models.
At a professional garage, they may use an ultrasonic machine to clean the injectors out. Those who have some mechanical skill can pull the injectors themselves, disassemble them, and clean the parts in an acetone bath and wire brushes.
Each injector typically costs $100–$1,000, with diesel and direct-injection units commanding top dollar. Because injectors require precision machining, part prices often dwarf labor on luxury models. Labor runs $110–$406 per injector, depending on engine accessibility and local shop rates.
This is because the injectors are not delivering the right fuel to the engine, which can cause the check engine light to become active. For example, if the fuel-air mixture is not correct, your car's O2 sensor will throw an error code resulting in an active check engine light.
Generally, diesel common rail injectors last between 150,000km and 250,000km, but this varies based on several factors. We've seen some fail as early as 120,000km, while others last beyond 400,000km with proper care. Key factors that influence lifespan include: Fuel quality.
Replacing fuel injectors is a detailed task, but with the right approach, you can handle it. If you're confident with tools and automotive work, follow this step-by-step guide to get the job done. While the cost of replacing fuel injectors can vary, doing it yourself can save you money.
The time it takes to replace a fuel injector or fuel injectors can range from under 1 hour to 4 hours, this will depend on a number of factors like your vehicle's make and model, year, and how many injectors need replacing.
5 Common Signs of a Failing Turbocharger
Diesel engines are robust machines that have longer lifespans than you might expect. The lifespan of an average diesel engine is anywhere from 400,000 miles to 1,000,000 miles, while the average lifespan of a gas engine is around 200,000 miles.
White smoke billowing from the exhaust pipe is a telltale sign of a blown head gasket. This occurs when coolant leaks into the combustion chamber and gets burned along with the air-fuel mixture. The result is thick, white smoke with a sweet smell due to the burning of antifreeze.
The worst things for a diesel engine involve neglecting maintenance (especially oil/filters), using poor fuel quality, allowing low fuel levels, overloading/lugging the engine, and not letting it warm up/cool down properly, all leading to contamination, excessive wear, turbo damage, and injector/pump failure due to high pressures and sensitive components. Contaminated fuel (water, dirt, high sulfur) is especially damaging, corroding parts and clogging filters in these high-pressure systems.
Cleaning is a much better option – fast, cheaper, and if you use the right solution, very effective.
Contamination & Clogging: Dirt, carbon, or poor-quality fuel can clog the injector, reducing fuel flow and causing misfires. Electrical Issues: Wiring or solenoid problems can prevent the injector from opening properly, leading to poor engine performance or a check engine light.