The AA has received complaints recently from motorists concerning laundered and sub-standard diesel.
The motoring organisation is advising people to buy carefully or they risk being hit with a costly repair.
“This is not a new phenomenon, but with current fuel prices so high and people feeling the pinch it does seem to be on the rise,” says the AA’s director of policy Conor Faughnan.
“It may be tempting when you see a fantastic price but you should only ever get your fuel from a reputable source. Regrettably we are hearing more anecdotal stories about this in recent months, including motorists who have faced costly repairs.”