Hello Paul, fuel prices have shot up past Shs6,500 a litre, and on my street the difference between the cheapest and most expensive station is now Shs300 to 400. My uncle insists the cheap fuel is ‘diluted’ and that it destroyed his pickup’s injectors. Is there any truth to this, and how would I know if bad fuel is damaging my engine before it is too late? Daniel
Hello Daniel, your uncle is not entirely wrong, but his information may be about a decade out of date. Fuel adulteration has been a concern for Ugandan motorists, but fuel-quality monitoring has improved. Let me explain what this means for you, especially with fuel prices at about Shs6,500 a litre.
Fuel adulteration was once a problem for Ugandan motorists, with unscrupulous dealers mixing kerosene with petrol or diesel to increase their profit margins. Poor-quality or contaminated fuel can damage a vehicle’s fuel system, particularly modern diesel engines with common-rail injectors and high-pressure fuel pumps. It can also contaminate engine oil, compromise its lubrication and protective properties, and cause serious wear or damage to engine components.
However, government efforts, including the Fuel Marking and Quality Monitoring Programme, have strengthened fuel-quality monitoring. Leading fuel dealers have also introduced quality-control measures throughout their supply chains. These include testing fuel at the source, storage depots and retail stations during offloading and, in some cases, every morning.
The Uganda National Bureau of Standards (UNBS) also monitors fuel quality and takes action against non-compliant operators. Nevertheless, these measures do not guarantee that every station or every batch of fuel is free from problems.
Why fuel prices differ
A Shs300 to Shs400 difference per litre between stations on the same street does not automatically mean the cheaper fuel is diluted or adulterated. Prices can vary because of differences in supplier contracts, operating costs, transport expenses, stock purchased at different prices and promotional offers.
A station on a busy highway, for instance, may sell larger volumes at a smaller profit margin, while another may have higher operating costs. Therefore, do not judge fuel quality by price alone, but remain cautious about suspiciously cheap fuel from unverified sources.
How bad fuel announces itself
An engine may show warning signs when it receives contaminated or poor-quality fuel. Watch for rough idling and misfiring, where the engine shakes while stationary or hesitates during acceleration. Knocking or pinging, which may sound like metallic rattling under load, particularly when climbing a hill, can also indicate abnormal combustion.
A sudden loss of power, poor fuel ecomy and black smoke from the exhaust may point to combustion problems. If the check engine light comes on shortly after refuelling, take it seriously. Difficulty starting or unexpected stalling may also indicate water or other contaminants in the fuel, although these symptoms can have other causes.
What to do if you suspect bad fuel
Stop buying fuel from the station in question until your concerns are investigated. If symptoms begin soon after refuelling, avoid repeatedly starting or driving the vehicle, particularly if the engine is knocking heavily, misfiring or stalling.
Have a qualified technician inspect the fuel system, check the fuel filter for contamination and test a fuel sample if necessary. Do not assume that adding an injector cleaner will solve the problem. If contamination is confirmed, the tank may need draining and the fuel filter replacing before you continue driving. If damage has already occurred, further repairs may be necessary, particularly on modern diesel engines with expensive injectors and high-pressure fuel pumps.
My advice is simple: buy fuel from established stations with verified pumps and valid UNBS verification stickers. Keep your receipts, especially when travelling, and record where and when you refuel. If symptoms develop soon afterwards, this information can help your mechanic investigate the cause. If you suspect adulteration, report it to UNBS through its official reporting channels.
Finally, tell your uncle that fuel-quality monitoring has improved, although this does not mean every fuel-quality problem has disappeared. If his pickup’s injectors failed, contaminated fuel could have been responsible, but ordinary wear and tear or another mechanical fault could also explain the failure. The failure alone does not prove that the fuel was adulterated.