Why Do Fuel Injectors Start to Deteriorate?

Posted on: 22 March 2022

Modern vehicle engines rely on fuel injection, forcing the petrol through microscopic holes within pencil-like injectors. These holes are incredibly small, and the fuel is more like a vapour by the time it reaches the combustion chamber. It's not difficult to imagine how problems could arise in such a delicate environment. What can happen if those holes become blocked, and how can you avoid that type of situation?

The Job of the Injector

Your engine will have a fuel injector for each cylinder, linked together as part of a common rail approach. The fuel is pumped from the tank and goes through a filter before it reaches the common rail, where it is pressurised and forced through those tiny nozzles to provide the perfect mixture for detonation.

Dirty Fuel

Fuel filters are very efficient and often need to be, as the quality of the petrol you get from your local service station may not always be top class. Also, tiny pieces of corrosion could break away from your tank's inside, falling to the bottom. If you get into the habit of running the tank low before filling up, some of the sediment may interfere with the system.

How Problems Arise

Some tiny particles will inevitably find their way through to the common rail. When they do so, they become trapped in the injector nozzle and can certainly affect performance. Furthermore, additional particles may begin to build up on the outside of the injector as it sits within the chamber. This happens when you turn the engine off, and the residual heat starts to vaporise any remaining fuel. As it does so, it will cause hardening deposits which will, once again, begin to block the injector.

Cleaning Solution

Think about adding some fuel additives from time to time that are designed for cleaning purposes. There are many available in the marketplace, so talk with your parts supplier for their advice.

Regular Servicing

Periodically, you should take your vehicle to a car servicing centre so that they can perform a full system service. As part of this work, they will remove the fuel injectors and clean them if at all possible. Sometimes, they will have seen their better days, though, and will have to be replaced in this case. When replacing, always use top-quality parts as they will have been specifically designed to last and cope with the severe conditions found within the engine.