Diluted petrol in Rome: why modern motorcycles are failing in droves

• Workshops report 25 to 30 percent more cases than before
• Petrol prices in 2026 climbed from 1.67 euros to most recently around 2 euros per litre
• The Guardia di Finanza seized 74 tonnes of non-compliant fuel in Rome alone

The tank is full, and yet the engine cuts out after a few kilometres. What at first looks like an electronics fault or overheating in the Roman high summer turns out in the workshops more and more often to be something else: water and deposits in the fuel. Research by the Italian news agency Adnkronos surveyed several mechanics in different districts of the capital in early August. Their accounts resemble each other so closely that the matter is now occupying authorities, consumer groups and politicians.

What is currently happening at Rome’s filling stations?

According to several Roman workshops, the number of vehicles with contaminated fuel in the tank has risen sharply over the past six months. Cars are affected just as much as motorcycles and scooters.

The reports come from very different neighbourhoods. Giancarlo Lanza, owner of a workshop in the Quadraro district, has worked in the trade for five decades and says: “In cinquant’anni di lavoro non mi era mai capitato di trovare auto con la benzina allungata con l’acqua, se non negli ultimi sei mesi.” In English: “In fifty years of work it has never happened to me to find cars with petrol cut with water, except in the last six months.” He also reports that there are people talking about cisterns diluted with water.

Roberto Federici, a motorcycle mechanic in Monteverde, describes the case of a filling station whose underground tanks contained water. Whether that was deliberate he cannot say, but the damage to the engines was considerable. Most recently he had two customers with the same problem on a single day. Romar Ponciano, who works at a motorcycle workshop on Corso Trieste, counts at least ten cases in recent months. Renato Di Nicolò from Casalbruciato puts the increase at 25 to 30 percent compared with before. In his workshop he showed a bucket of diesel in which the contaminants settled clearly visible under the beam of a torch.

Why are modern scooters and motorcycles hit particularly hard?

Modern two-wheelers react more sensitively to contamination because they run on precision fuel injection systems rather than carburettors. Even small amounts of water or sand can clog injectors or cause the fuel pump to fail.

A carburettor is a purely mechanical component that mixes fuel and air and tolerates a fair amount of dirt in the process. An electronic injection system works with very fine nozzles and high pressure. What used to pass through unnoticed today brings a machine to a standstill within a few kilometres. Federici describes it like this: “In caso di benzina di scarsa qualità, i motorini, le moto e gli scooter di ultima generazione si fermano poco dopo aver fatto rifornimento, te ne accorgi subito.” Translated: “With poor-quality petrol, the latest generation of mopeds, motorcycles and scooters stop shortly after refuelling, you notice it immediately.”

In the workshops this then looks very different from case to case: cars arrive on a tow truck, scooters are pushed in. The work involved is similar either way. Drain the tank, clean the fuel system, and in the worst case replace components.

How does water get into the fuel in the first place?

There are several possible explanations for water in the fuel, ranging from leaking filling station tanks to condensation and contamination elsewhere in the supply chain. A single cause cannot yet be identified with certainty.

Ponciano describes a mechanism that requires no ill intent: sludge, fine dust and sand settle on the bottom of the underground cisterns at filling stations. When a tank is run almost empty, the pump draws these deposits along with the fuel and delivers them straight into vehicle tanks. Also conceivable is moisture entering during storage, or problems during transport.

It also remains open whether the phenomenon really is increasing on a large scale or whether the reported cases are concentrated in a few districts. Because modern vehicles react more sensitively, the same contamination may today simply lead to a visible defect more often than it did twenty years ago.

Are high fuel prices behind it?

There is no proven link between the rise in fuel prices and the contaminated deliveries. The mechanics surveyed explicitly speak of a suspicion, not of evidence.

The figures are striking nonetheless. The average price of petrol in Italy rose from 1.67 euros (around 1.93 US dollars) per litre on 1 January 2026 to 1.94 euros (around 2.24 US dollars) on 1 June. Diesel went from 1.65 euros (around 1.91 US dollars) to more than 2 euros (around 2.31 US dollars) over the same period. During the big travel wave in early August, petrol again brushed the 2-euro mark and diesel climbed back towards 2.10 euros (around 2.43 US dollars).

The sceptics’ reasoning is simple: the more expensive a litre is to sell, the greater the financial incentive for dubious operators to tamper with quantity or quality. So far this assumption has not been proven. For motorcyclists heading to Italy in summer, it adds another element of uncertainty on top of already higher travel costs.

The finance police are inspecting Rome’s filling stations

On 5 August 2026 the Guardia di Finanza launched a large-scale inspection campaign at filling stations in Rome. The focus was above all on diesel, which investigators consider easier to adulterate.

Italy’s Minister for Enterprise and Made in Italy, Adolfo Urso, confirmed the operation during a question time in the Chamber of Deputies and explicitly linked it to the mechanics’ accounts. Colonel Daniele Corradini, commander of the first group of the finance police in Rome, explained: “Le verifiche riguardano in particolar modo la qualità del carburante erogato che, in determinati casi, risultava allungato con acqua o con altri prodotti.” In English: “The checks concern in particular the quality of the fuel dispensed, which in certain cases turned out to have been cut with water or other products.” According to him, the Rome provincial command alone seized 74 tonnes of non-compliant fuel in the first six months of the year. The inspections are continuing through August.

Sergeant Chiara Pusceddu of the third operational unit of the Roman finance police described how such an inspection works. First, licences are checked and it is verified whether the posted prices, the prices actually charged and those reported to the ministry portal all match. Then comes the so-called “steccata”: an iron rod is lowered to the bottom of the cistern. A special paste on the rod indicates whether water or oil is sitting there alongside the fuel. Finally, six samples of around one litre each are drawn directly from the nozzle into aluminium cans, sealed, catalogued and sent to the laboratory for analysis as well as to the customs and monopolies agency.

What do consumer groups and politicians say?

Consumer associations are calling for blanket inspections and point out that selling adulterated fuel can constitute several criminal offences. Road safety is also cited as an argument.

Gianluca Di Ascenzo, president of the consumer protection organisation Codacons, frames it as follows: “La vendita di carburanti annacquati è un grave illecito che configura diversi reati.” In English: “The sale of watered-down fuels is a serious offence that constitutes several crimes.” He names commercial fraud, fraud and breaches of tax regulations. A vehicle owner can hardly tell at the pump that something is wrong, he says, because proving water in the fuel requires an expert.

Vincenzo Donvito, president of the consumer association Aduc, traces the problem back to a lack of inspection policy. Liability towards the injured party lies with whoever sold the product, he argues, even if an operator might object that they have nothing to do with the delivery of the fuel. He additionally advises filing a report with the competition authority for unfair commercial practices.

Daniele Rondinelli, president of the Andac association, points to the safety side: a vehicle that suddenly loses power or stops in the middle of traffic can become dangerous for all road users. From the political side came the proposal to start with spot checks immediately, because legislation would take too long. Alberto Di Rubba, responsible for the automotive sector at the Lega party, points to the deterrent effect: if 50 filling stations were inspected, even the operator who is not inspected might think twice about their approach. For those affected, the damage comes with the added annoyance of having to pay the workshop for draining and cleaning the tank.

What to do if your motorcycle cuts out after refuelling?

If a motorcycle stops shortly after refuelling, you should not keep trying to restart the engine. That way less contaminated fuel reaches further components of the system.

The fuel receipt is also important, because it is the only way to establish later where the fuel was bought. If possible, a sample of the contaminated fuel should be kept as evidence. Mauro Antonelli, head of the research department at the Unione Nazionale Consumatori, recommends sending a claim by registered letter or certified email to the filling station operator, with the relevant oil company copied in. If other reports are already on file, such a claim is sometimes settled directly through the insurer. If it is rejected, the route through the courts remains. Antonelli stresses that the complaint should be made immediately and that the complete documentation, including the receipt, should be kept. According to him, the consumer organisation receives several reports of this kind every year.

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