Teaching my kids abouts cars
About Me
Teaching my kids abouts cars

I think it's really important to know a bit about the internals of a car, so that when you are getting your car serviced you can talk intelligently with the auto technician. As well, there are many easy DIY jobs you can do on your car to save your some money which can make all the difference when you are young and starting out. This site is where I am recording everything I am teaching my kids about auto servicing, and because I think it will be useful to many other families as well. I hope you find it useful for your family.

Teaching my kids abouts cars

How to Diagnose a Faulty Diesel Engine

Kenzi Jacobs

Many owners of vehicles with a diesel engine assume that it is easy to diagnose and correct the problem, if the vehicle is taken to a garage. This is simply not the case. While it is true that modern technology means that modern diesel vehicles can be connected to the computer to display fault codes, these fault codes are usually not the root cause of the problem. This article looks some common diesel engine faults and how you can identify them.

Faulty Injector

In a diesel injector, it is critical to have proper excessive flow returns. This means that any excessive fuel can be gathered and returned to be reused. Many excessive fuel return parts can become damaged, resulting in the injector not being able to get rid of any excessive diesel. This, in turn, leads to a decrease of rail pressure and can cause the injector to struggle to start or not start working at all.

In some diesel engines, white smoke can be caused, while the vehicle is idling, by nozzle dribbling; this causes the injection system to lose unburnt fuel, and produces the smoke.

Low Fuel Pressure

This is probably the area that causes most problems with regards to the fuel supply. The two most common issues here are:

  • A poor supply of fuel to the injector, pump or rail
  • The injector, pump or rail is not holding sufficient fuel to enable proper operation.

The proper way to diagnose this issue is by beginning at the fuel tank and checking the diesel supply that is going to the pump. Then, check if the pump is actually delivering diesel. Testing the delivery of the pump requires the removal of the supply pipe from rail to pump; a finger can be used to cover the end of the pipe while the engine is cranked, and the pressure can be checked.

Interpret the Smoke

More credence than you may think is given to the different colors of smoke that indicate an issue with a diesel engine when it is faulty. If you can identify the color of the smoke, you can have an easier time explaining what's wrong with the vehicle to a mechanic. There are three main types of smoke:

  • Black smoke—faults with the injectors, injector pump, or cylinder head
  • Blue smoke—worn cylinder rings, valves or seams of valves or the injector is mixing oil with fuel
  • White smoke—low engine compression, pump or engine mistiming or petrol or water is present in the fuel.

As people rely on their vehicles for everyday life, many will automatically take their faulty vehicle to a diesel mechanic like Hi Tech Diesel Injection Pty Ltd. Consider calling on one as well to ensure your car is taken care of.