A blocked AdBlue injector stops the right amount of fluid getting into the exhaust, and the ECU notices almost straight away. First you’ll usually get a warning light, sometimes a mileage countdown not long after, and if it’s left too…
A Mercedes AdBlue system fault means the engine management system has detected a problem within the SCR (Selective Catalytic Reduction) emissions system and the vehicle will count down to a no-restart lockout if the fault is not resolved. Mercedes diesel…
Once an AdBlue countdown hits 0 miles, the engine won’t restart once you switch it off. That’s it. Nothing’s actually broken, not in the way a flat battery or a snapped cambelt is broken. The ECU has made a decision…
Seeing P204F on a scanner doesn’t tell you much about what needs fixing. It’s a reductant system performance code, which is a fancy way of saying the AdBlue side of your SCR system isn’t doing what the engine computer expects…
If there’s a white, crusty residue forming around your AdBlue filler cap and an SCR warning light staring back at you from the dash, you already know something’s wrong. What you probably don’t know yet is whether it’s fixable, or…
Bit of a maddening one, this. You’ve filled the tank, you watched the pump cut off on its own, maybe you even double-checked with the dipstick or the gauge. And the warning’s still sat there on the dash like it…
Do AdBlue problems vary between manufacturers? Yes, quite a bit. Every SCR system does the same core job injecting AdBlue into the exhaust to cut nitrogen oxide emissions but the warning messages, the parts most likely to fail, and how…
Your dashboard flashes up an AdBlue warning and suddenly you’re doing mental maths about how many miles you’ve got left before the car refuses to start. It’s one of the most stressful warnings a diesel driver can see, mostly because…
If your AdBlue warning light has come on, your van’s gone into limp mode, or you’re staring down a countdown to zero starts on a depot forecourt, you need answers not a lecture. This guide covers everything UK van, HGV…
