Swapped for the ULEZ, now learning about AdBlue
When the ULEZ reached Thornton Heath in August 2023, a lot of drivers replaced older diesels with Euro 6 models to avoid the daily charge. It was a sensible move, but it brought a system many had never dealt with before. Most Euro 6 diesels that use AdBlue have a separate tank, a blue filler cap and a set of warnings that mean different things, and it's easy to mistake a fault for a simple top-up.
A low-level warning asks for fluid and should clear after a refill. A warning that stays after topping up, or one that comes with the engine management light, means a fault. A countdown to no-start means the ECU has decided the fault must be fixed and will enforce it. On cars used for everyday work around the town centre, crawling along Brigstock Road behind buses or queuing at Thornton Heath Pond, crystallised injectors and tired NOx sensors are typical causes. Private hire drivers and staff driving in to Croydon University Hospital put up big mileages in exactly these conditions.
We start by reading the codes and explaining them in plain terms. Then we test the dosing, pump, heater and fluid quality to confirm the cause. Because many of these cars were bought used, we also look for signs of earlier repairs or tampering, since a system that has been interfered with needs putting right before new parts will work reliably. The written quote comes before any work.
From the clock tower it's about 5 miles to us. Head to Thornton Heath Pond, take Thornton Road to the Lombard roundabout and follow the A236 across Mitcham Common to Hackbridge. If you're near Thornton Heath Leisure Centre or St Alban's Church, pick up the same route at the Pond. On Crystal Palace home match days, keep away from the roads around Selhurst Park when you set off. Every repair carries a 3-month workmanship warranty, and collection can be arranged if the car won't restart.