NAIROBI, Kenya, Apr 6 — A shipment of Premium Motor Spirit (PMS) cited in correspondence by former Petroleum Principal Secretary Mohamed Liban has sparked concern over the potential effects of off-spec fuel on vehicles, even as authorities investigate regulatory waivers and alleged corruption. Althought is no confirmation that the shipment anticipated on Saturday arrived, correspondence on waiver request indicates deviations from Kenyan fuel standards with the Trade Ministry proposing comingling of the fuel with existing stock to manage the risk.What is off-spec fuel?Off-spec fuel refers to petrol or diesel that does not meet required chemical and safety standards, including levels of oxygenates, octane boosters, manganese, sulphur, and benzene. These components are critical for engine efficiency, emissions, and long-term reliability.Potential effects on vehicles1. Reduced engine performance and fuel efficiencyLower oxygenates in petrol can lead to incomplete combustion, meaning the engine uses more fuel to produce the same power, lowering mileage and efficiency.2. Engine misfires and damage to spark plugsExcess manganese or other metal additives can leave deposits in fuel injectors and spark plugs, causing misfires, rough idling, or stalling over time.Fuel scandal: Liban, Sang, Bargoria face 10-year jail risk as charges loom3. Catalytic converter and emissions issuesHigh benzene or sulphur levels can corrode catalytic converters and other engine components, increasing harmful emissions and risking future regulatory non-compliance.4. Long-term wearEven if a car seems to operate normally, repeated use of fuel outside specifications can accelerate wear on pistons, valves, and internal engine components, shortening the lifespan of the engine.5. Potential safety risksEngines running on improperly blended fuel can overheat, stall unexpectedly, or exhibit other performance issues, creating possible hazards for drivers.Why it mattersInvestigators are examining waivers granted by officials to allow deviations on oxygenates, manganese, sulphur, and benzene in the PMS cargo referenced in Liban’s March letter. The inquiry centers on whether these regulatory exemptions were exploited to introduce off-spec fuel under the guise of national supply management.While the fuel’s arrival remains unconfirmed, the case highlights the risks posed when standards designed to protect vehicles and consumers are relaxed.