--- title: Southwark: AdBlue in a Diesel Tank, Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/southwark-greater-london/ location: Southwark county: Greater London latitude: 51.502750 longitude: -0.096820 service: AdBlue in a Diesel Tank updated: 2026-10-15 --- # Why It Occurs and How to Prevent It: AdBlue in a Diesel Tank in Southwark If AdBlue is already in your diesel tank, stop reading for a moment: leave your engine and the ignition off and phone 0333 366 0103. A drain plus a full flush, carried out right where your vehicle stands around Southwark, is usually all it takes when found before your engine runs. Reading in advance? In that case what follows covers why it happens and how to prevent it ever happening. ## Two fillers, two tanks: AdBlue in a diesel car Many modern diesels in Elephant and Castle, like those in Southwark, carry on two fluids; the engine gets just your diesel. AdBlue goes to your exhaust, where it is sprayed into the gas to fresh it, and it lives in a tank of its own. Each tank comes with one filler of its own. On a lot of motors the two sit side by side under the same flap; on others the AdBlue filler is in your boot or under the bonnet. At the petrol pump, your diesel side gets filled constantly. Much less often, the AdBlue side gets topped up — mostly from a bottle, by someone working out where it goes. It's in that gap that the slip lives. ## How AdBlue in your diesel tank takes place in Southwark Three things tend to come together, and carelessness is seldom one of them. On a driveway off Southwark Bridge Road before work, or in the car park at The Lord Clyde heading home: that is where the hurried top-up happens. Why the rush? As AdBlue gets low the car warns you, and once it is empty, limp mode follows. The old car's filler is where the hand reaches — but a hire car, a new vehicle or a company car keeps the fillers elsewhere. That's the second thing: a strange vehicle. No part stops the pour after it has started, because a bottle with a spout goes into a diesel filler as readily as an AdBlue one. The bottle fits. The same few seconds settle it, in the middle of Southwark or out in The Borough. ## Which filler is for AdBlue, and which for diesel? Whether a Southwark forecourt or a drive over in Blackfriars, spend a couple of seconds over these before anything goes in. - Position misleads; the cap doesn't. AdBlue ones tend to be blue or carry the name "AdBlue" — diesel ones usually do not. - Check the size: the smaller neck is, on many motors, the AdBlue one. - The flap. Look inside the fuel flap for a label. Plenty of cars say there which fuel goes where. - The handbook shows which it lives when your filler is not next to your diesel cap: the boot, or under the bonnet. - Picking up a hire or company car, perhaps at the car park at London Waterloo East? Check with whoever drove it last before leaving, rather than when the light comes on. ## Topping up AdBlue without it reaching your diesel tank Wherever across Greater London the light comes on, this is a routine for that day. - Park then switch off. Not on a slope, not with the engine running, and not in a rush on the side of Copperfield Street. - Find the AdBlue filler, check the cap, and say the name "AdBlue" aloud as you unscrew it. It seems daft. It does the trick. - If both sit under one flap, check your diesel cap is still closed before you lift the bottle — then leave the car on. - Using the bottle's own spout, tip slowly — and stop when it is full or the bottle is empty. - Close the cap and check once more. Make sure the diesel cap was never opened. Only then start the vehicle. Discover at the second or third stage that AdBlue went into the wrong filler? That is where you stop. Never go on to stage five. ## AdBlue in your diesel tank already, in Southwark? Brief list, then. Top of it: your engine stays unstarted. Do not switch the ignition on; on plenty of diesels that alone runs the fuel pump. AdBlue does not mix with diesel — it sinks to the bottom of your tank, where the fuel is sucked from — so do not top up with diesel to dilute it. The staff at Shell, Texaco or any forecourt will normally help pushing your car away when you ask. If you're on your own driveway in Southwark, leave the vehicle where it stands. Already started? Pull over once it is sensible, then switch off. Southwark lies under 10 miles from the M1; on it, use the next junction. Mileage matters — a quick hop across Southwark is a smaller job than driving under a mile towards London — so say about how far it went. ## What happens when our technicians arrive in Southwark Anywhere the vehicle came to rest, be it by Charles Dickens Primary School, beside The Evelina Hospital for Sick Children or at home, our van travels to it. Which fluid was put in, the quantity, and whether it ran: we ask because those replies set both work and price. No one sets off until you've had the quote over the phone. Next: draining, then a thorough flush of the entire system. Not like petrol, AdBlue forms crystals and eats at certain fuel-system metals, and neither washes away by itself. That is why it counts more. Your filter is cleaned, or replaced where it needs to be; fresh diesel goes in; and the car is tested. We do not go until it has been started and is running smoothly. Unstarted cars usually mean a half-hour visit from the moment we arrive. The equipment is safe on a live filling station, and quiet enough for a driveway late at night. Payment happens on the day, not upfront, and you are given the paperwork your insurer wants: an engineer report and a VAT invoice. Many insurance policies include misfuelling cover, so it's worth checking yours while we're on the way. ## About Southwark itself Southwark is a locality in central London, situated on the southern bank of the River Thames, with The Borough and Bankside to the west and North Southwark to the east. Southwark sits at a low elevation of around 9 metres above sea level, close to the heart of the city. Southwark is characterized by its predominantly flat-type housing and its proximity to major London landmarks. Southwark is home to a diverse population of approximately 8912 residents. ## AdBlue drains round Southwark, and Greater London beyond Throughout SE postcodes, the vans that cover Southwark — a neighbourhood — work the nearby locations too, Bankside and North Southwark among them. Fastest of all: give a SE1 0 postcode for our van. No need to move the vehicle. Anywhere it stands — beside The Borough Welsh Congregational Chapel, in a lay-by heading to Mint Street Park, on a drive — that is where it gets drained. Assuming won't help behind Cøpperfield, close to a boundary, or somewhere hard to pin down; ring and check. ## For Southwark people, the short version Always, the cap; after that, the tip. Still AdBlue in your diesel tank? Petrol in Diesel will empty it where it stands, wherever around Greater London: switch it off and ring 0333 366 0103.