Some people say “Take care of your tools and they will take care of you“. This well-known proverb is true in many aspects of life. One of them are gas installations for diesel engines. Our system – Fuel Fusion – can be used for many years, bringing significant savings, but it must be properly serviced. Every user should remember to perform regular inspections. Only then will you be sure that the installation is safe, tight and effective. Timely inspections are also a condition for maintaining the warranty for filters (50,000 km or 750 hours of operation in gas) and injectors (100,000 km or 1,400 hours of operation in gas). People who are more familiar with the subject may have already noticed that in this respect, the installation for diesel engines is not much different from systems dedicated to petrol vehicles – regular inspections are a must.

When should you service Fuel Fusion?

Regular Fuel Fusion inspections should be performed every 50,000 km in the case of vehicles, and every 750 mth on gas, in the case of immobile machines, e.g. power generators or chargers.

Fortunately, you don’t have to remember all this, write anything down in your calendar or make complicated mathematical calculations! When purchasing, you will receive a cheat sheet from us in the form of a service book. You will find all the necessary information there.

So do you need to check it regularly to make sure when it’s time for the next inspection? Not necessarily!

Of course, the service book will be an excellent hint and will allow you to prepare well in advance for the inspection.

What if you forget about it? Will you miss the opportunity to get your inspection done? Of course not. When we said Fuel Fusion works automatically, we weren’t lying. Our installation will also provide you with support in this area. If needed, Fuel Fusion will clearly communicate its needs to you. To transmit messages to you, it uses the diodes on the switch.

When the installation reports a problem

The switch doesn’t just turn Fuel Fusion on and off. The diodes on it inform us about the approximate amount of gas in the cylinder or the need to take service actions. For example, when it is time to carry out an inspection, the so-called “service limit” message, i.e. the third (II), fourth (III) and fifth diode (IIII).

In the same way, the installation will also inform us about other possible problems that require diagnostic work. What are Fuel Fusion error codes?

1. only the second diode (I) is lit – low current of gas injectors – there is probably an interruption in the injector circuit, the controller board or the injector is damaged,

2. only the fourth diode (III) is lit – the reducer temperature is outside the range,

3. the second and fourth diodes (II and III) are on – the exhaust gas temperature is too high.

Apart from the situation when only the first diode (R) is lit, each message requires carrying out a diagnostic test at an authorized workshop.

What to do if only the first LED is lit? As we said – such message means that the gas pressure in the cylinder is too low. How to solve this problem? It’s easy! You need to fill up with gas.


  1. if the R and I diodes are lit, we have about ¼ of the cylinger filled with gas,

2. R, I II diode means the cylinder is half full,

3. R, I, II, III to ¾ cylinder,

4. R, I, II, III and IIII diodes mean that the cylinder is full.

What does a routine inspection of a Fuel Fusion look like?

Cyclical technical inspections, unlike diagnostic tests related to a specific error code, consist of routine activities that allow you to confirm the correct operation of the entire installation.

During the examination, every, even the smallest element is checked. Although we have never had any of the Fuel Fusion screws come loose, all of them are checked for this every time. The workshop employee also verifies the condition of the elements fastening the installation elements. This is very important for safety reasons – it has happened before that some mountings have become bent, e.g. as a result of careless driving.

Another extremely important element of the tests is checking the gas main and high-pressure lines. In this case, it is mainly about checking the tightness of the elements responsible for gas flow. Making sure everything is tight helps you avoid gas leaks, which can cause financial loss and, in extreme cases, be potentially dangerous.

After every 50,000 kilometers or 750 mth of the installation in gas, it is necessary to replace the volatile phase gas filter. If we neglect this activity, the filter could become clogged, which could significantly reduce the efficiency of the installation or completely prevent gas flow. In the case of Fuel Fusion compatible with LPG, it is necessary to replace two gas filters – one at the reducer and one for the volatile phase. Propane-butane requires two filters because its state changes from liquid to volatile in the installation. During this process, impurities precipitate.

It is also necessary to replace gas injectors on time. If they are not replaced in time, they may be damaged, resulting in uncontrolled gas flow. Such a situation could cause an increase in exhaust gas temperature and, in extreme cases, lead to knocking combustion, which is dangerous for the engine. Of course, we are talking about the worst possible, unlikely scenario here. If the exhaust gas temperature began to rise, the EGT probe would activate, sending a message to the controller, which would reduce the gas dose or turn off the entire gas installation.

Every 200 thousand kilometers or 2,800 mth on gas, the reducer should be checked. In many cases, just adjusting it is enough. However, if the pressure inside is too high and the workshop employee is unable to adjust it, the element must be replaced. The reducer should also be replaced with a new one if the membrane is damaged and gas escapes through the vacuum port. In this case, the smell of gas will remain in the vicinity of the Fuel Fusion. The reducer also qualifies for replacement if there are visible leaks or other signs of damage, but this happens very rarely.

Diagnostic examination is not only about purely physical activities. It is also necessary to check the correct operation of the controller. To do this, it is necessary to connect the installation to the Fuel Fusion software and check:

    1. what is the gas pressure in the cylinder,
    2. what is the boost pressure,
    3. whether the rotational speed is consistent with the actual engine speed,
    4. what is the temperature of the reducer,
    5. whether Dual Fuel mode works properly.

How to make sense of it all?

The graphic below will be helpful:

Who can perform a diagnostic test?

We now know when to go for an inspection. We should also answer the question – where should we go to carry out the necessary service work?  Diagnostics of the Fuel Fusion cannot be performed by any car mechanic. The test is carried out only in workshops that have completed all formalities and have been entered on the list of authorized workshops maintained by ITS (Motor Transport Institute).

Legalization of the cylinder

A separate topic is the legalization of the gas cylinder. According to Polish law, an LPG gas cylinder can be used for 10 years from the date of production. After this time, it can be replaced with a new one or the so-called legalization, i.e. carrying out another technical examination carried out by institutions authorized by the Transport Technical Supervision.

We have an identical situation in the case of CNG cylinders. In their cases, the approval is also not unlimited. If we want to use the cylinder for longer than 10 years, we must have it tested.


Just like gas installations for gasoline engines, Fuel Fusion requires regular inspections. It is necessary to check the tightness of individual elements and the durability of its mounting elements. The responsibility of the owner of a vehicle or machine with a Fuel Fusion also includes regular replacement of consumables, such as filters or injectors. If you neglect this duty, the installation may stop working or become much less effective. Timely inspections make sure everything is working exactly as it should. The diagnostic test should be carried out in an authorized workshop entered on the ITS (Motor Transport Institute) list. Owners of gas installations should also remember about the deadlines for LPG and CNG cylinders. When the legalization of an LPG cylinder comes to an end, the technical inspection must be performed again or the cylinder should be replaced with a new one.