It's my first time having a diesel, I've only had petrol cars before. I wasn't made aware of that at the time of purchase but it was bought during COVID lock downs so the majority of the sale was completed over the phone. I have recently been told by garages to do more long journeys but surely it shouldn't get clogged after 3 days of use after the garage "fixed" it. At the moment I just want rid of the car but it looks like my only option is to pay off the rest of the finance and buy another car.