Tuning Fiat Ducato CNG and petrol. Need advice!!!

[Adbaba]

Hi i recently bough a Fiat Ducato 2017 136 Horse power which runs on CNG and has a 14,5 liters Petrol backup. When the car runs on CNG the car works fine and has no speed limit whatso ever. But as soon as it switches over to the petrol fuel the it has a seed limiter on it. The maximum speed goes down from 160 km per hour to 90km per hour. I have tried a lot of things like adjusting the speed limit through the Multiscan from to nussent (which basically means no speed limit. An offical Fiat repair garage tried something as well.

After these unsuccesfull attempts i went to 3 different tuning companies in the Netherlands and one in Belgium. All of them insured me that they could fix the problem, but in the end they couldn't. According to Fiat the speed limit for when it runs on petrol is only there to make sure the driver goes to a nearby CNG gast staion and uses the primary fuel to drive the car.

I have looked at a lot of different websites for the answer, but it could not find anything. Does anyone has an answwer to this problem?????

 

[the green vanper]

Hello,

Happy to see another Ducato Natural Power owner

But sad to tell, there's no solution to this problem. It's not a bug, it's a feature, as the IT specialists say

In fact it is related to combustion characteristics differences between the natural gas and petrol. The van is designed to run on natural gas, petrol is being a reserve fuel only. From the same reason it is very hard to adapt the engine to run on LPG (it will run, but same as on petrol). The only possibility is to change completely the map in the injection ECU and adapt it to LPG / petrol. But then running it on natural gas would lead to a disaster.

 

[Adbaba]

Hello,

Happy to see another Ducato Natural Power owner

But sad to tell, there's no solution to this problem. It's not a bug, it's a feature, as the IT specialists say

In fact it is related to combustion characteristics differences between the natural gas and petrol. The van is designed to run on natural gas, petrol is being a reserve fuel only. From the same reason it is very hard to adapt the engine to run on LPG (it will run, but same as on petrol). The only possibility is to change completely the map in the injection ECU and adapt it to LPG / petrol. But then running it on natural gas would lead to a disaster.

Ahh

Hello,

Happy to see another Ducato Natural Power owner

But sad to tell, there's no solution to this problem. It's not a bug, it's a feature, as the IT specialists say

In fact it is related to combustion characteristics differences between the natural gas and petrol. The van is designed to run on natural gas, petrol is being a reserve fuel only. From the same reason it is very hard to adapt the engine to run on LPG (it will run, but same as on petrol). The only possibility is to change completely the map in the injection ECU and adapt it to LPG / petrol. But then running it on natural gas would lead to a disaster.

Finally someone who can give me a clear answer. I had one last appointment at Fiat themselves, because they don't believe me that the speed limit for the petrol part can't be removed. This is very annoying , because i have ordered a 47 liter custom made petrol tank. The built in petrol tank is a nbackup and only has 14,5 liters in it. Next to this i have made an appointment at an offical CNG garage. When you remove the spare tyre, you can add like 15 to 17 kg of extra CNG cilinders. With these extra cilinders in place my total capacity goes up to like 50 to 53 kg of CNG. That should be enough to have a radius of 450 tot 550 kilometers and with the petrol tank i can easily upgrade this to 850 to 900 km. The only downside is that when going on a long journey i have to make sure there are enough cng stations on my route or take the option of only going at a speed of 90 km per hour on petrol. Have you made any modifications to your ducato??

 

[the green vanper]

That is what I was told in a workshop specialized in CNG installations, one of the three in Poland that are able to exchange the CNG installation to LPG. Which of course voids the warranty (if there's one) and the ecological concept (if you want to have it).

Yes, the 2 extra cylinders were an option from the beginning of the x250 Natural Power version as far as I remember. I was very much counting on having them (because of the extra range), but finally I'm very happy that the van has only the 5 standard cylinders due to the weight of the cylinders. The small cylinders should weigh around 60 kgs each as far as I know. My van has only something like 900 kgs of loading capacity. Empty. Without any extra equipment that needs to be installed. Water tanks, leisure batteries, solar panels + roof rack... + my girlfriend and myself... I'm planning a very lightweight construction mostly in aluminium (the box is all aluminium, too). And loosing some weight myself haha

Then, from all the ads I've seen online for used Natural Power Ducatos, only one got the extra cylinders. It had like 650 tkms on the clock The one I bought several months later had only 99 tkms. So, a huge difference. When I'll need to replace the cylinders (they have 'only' 20 years of lifespan) I'll try to buy and install the composite cylinders, which are much, much lighter (like four - five of them weigh as much as one made of steel). Hope they will be available at the time

I also know that people are installing standard fuel tanks from a diesel version, but it requires an adaptation of the muffler. That's how I got an original muffler with only 10 tkms for 45 EUR only. Mine is completely rusted...

The EU law requires that a single fuel car / van has a reserve fuel tank capacity smaller than 15 liters. I'm insisting on keeping the van legal to be able to maintain the advantages of an ecological vehicle. That was one of the reasons I've chosen the Ducato over the Sprinter NGT (which is bi-fuel). But I'm planning on having a 15 liter jerrycan for fuel in the garage

When entering a country with low natural gas stations coverage I will just put fuel in it.

From my experience I count that with all the equipment (so almost 3500 kgs) the CNG range will be around 300 km but with a max speed of 100 km/h. At least with the box which is installed on my van. The consumption gets much higher when you increase the speed. So the extra 100 kms + eventually the other ones on gasoline (tank + jerrycan) shall do the job.

 

[Bb261299]

That is what I was told in a workshop specialized in CNG installations, one of the three in Poland that are able to exchange the CNG installation to LPG. Which of course voids the warranty (if there's one) and the ecological concept (if you want to have it).

Yes, the 2 extra cylinders were an option from the beginning of the x250 Natural Power version as far as I remember. I was very much counting on having them (because of the extra range), but finally I'm very happy that the van has only the 5 standard cylinders due to the weight of the cylinders. The small cylinders should weigh around 60 kgs each as far as I know. My van has only something like 900 kgs of loading capacity. Empty. Without any extra equipment that needs to be installed. Water tanks, leisure batteries, solar panels + roof rack... + my girlfriend and myself... I'm planning a very lightweight construction mostly in aluminium (the box is all aluminium, too). And loosing some weight myself haha

Then, from all the ads I've seen online for used Natural Power Ducatos, only one got the extra cylinders. It had like 650 tkms on the clock The one I bought several months later had only 99 tkms. So, a huge difference. When I'll need to replace the cylinders (they have 'only' 20 years of lifespan) I'll try to buy and install the composite cylinders, which are much, much lighter (like four - five of them weigh as much as one made of steel). Hope they will be available at the time

I also know that people are installing standard fuel tanks from a diesel version, but it requires an adaptation of the muffler. That's how I got an original muffler with only 10 tkms for 45 EUR only. Mine is completely rusted...

The EU law requires that a single fuel car / van has a reserve fuel tank capacity smaller than 15 liters. I'm insisting on keeping the van legal to be able to maintain the advantages of an ecological vehicle. That was one of the reasons I've chosen the Ducato over the Sprinter NGT (which is bi-fuel). But I'm planning on having a 15 liter jerrycan for fuel in the garage

When entering a country with low natural gas stations coverage I will just put fuel in it.

From my experience I count that with all the equipment (so almost 3500 kgs) the CNG range will be around 300 km but with a max speed of 100 km/h. At least with the box which is installed on my van. The consumption gets much higher when you increase the speed. So the extra 100 kms + eventually the other ones on gasoline (tank + jerrycan) shall do the job.

Hi!

Slightly related question, i hope you can help me.

I have a Ducato Natural power 3.0 power and a company converted it to lpg, however didn't do a proper job and no one seems to know what to do. It's a mess tbh, because some cables are just cut off and idk what is what. It runs on lpg but way to rich and it's restricted because it thinks the tank is empty (it also seems to be restricted due to the emergency loop due to the empty tank or other reasons).

However I saw you said something about how difficult it was to convert it to lpg. What makes it so difficult? I saw some polish video's of conversions but I do not understand polish unfortunately. Is it possible to do it with only reprogramming the ecu or do I need to do a lot more?

Hope you can provide me with some answers, thnx in advance!

 

[the green vanper]

I can't remember what is the precise problem. As far as I remember, there is a difference between combustion temperature on CNG and gasoline.

The official documents say that the power on gasoline is limited to maintain a moderate fuel consumption (which is huge, like 18l/100 km if I'm not mistaken).

I could give you the contact to the workshop I've mentionned, but I don't know if they speak English. Perhaps they would be willing to advise by mail.

 

[Bb261299]

Thank you for your answer. I can give it a try, if you can share it would be amazing!

 

[Bb261299]

I can't remember what is the precise problem. As far as I remember, there is a difference between combustion temperature on CNG and gasoline.

The official documents say that the power on gasoline is limited to maintain a moderate fuel consumption (which is huge, like 18l/100 km if I'm not mistaken).

I could give you the contact to the workshop I've mentionned, but I don't know if they speak English. Perhaps they would be willing to advise by mail.

Thank you for your answer. I can give it a try, if you can share it would be amazing!