--- title: AdBlue in a Diesel Tank Highbury: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/highbury-somerset/ location: Highbury county: Somerset latitude: 51.236930 longitude: -2.450160 service: AdBlue in a Diesel Tank updated: 2026-10-09 --- # Highbury: How Does AdBlue End Up in a Diesel Tank, and How Do You Avoid It? AdBlue already in the diesel tank? In that case put this page aside a moment, keep the ignition and motor off, and call 0333 366 0103. A drain and a full flush, done just where your vehicle stands in Highbury, is normally what it takes when found before the engine runs. If you're reading before it has happened, the remainder of this page is about why it happens and how to make sure it does not. ## Two fillers, two tanks: AdBlue in a diesel car Plenty of modern diesels around Towns End, as well as Highbury, carry on two fluids; the engine takes just the diesel. AdBlue goes to your exhaust, where it is sprayed into the gas to clean it, and it lives in a tank of its own. Separate tanks, separate fillers. Under one flap, next to each other: that's the layout on a lot of cars. Elsewhere, AdBlue's filler sits beneath the bonnet or in your boot instead. Topping up your diesel side at the petrol pump happens constantly. Rarely filled, AdBlue normally comes out of a bottle, poured by someone who must stop and think what filler to use. Mistakes happen in that gap between them. ## How does AdBlue in your diesel tank happen in Highbury? Three things tend to come together, and carelessness is rarely one of them. The warning comes first. As AdBlue runs low the car tells you, and if it runs out altogether, the car drops into limp mode. So the top-up is done in a hurry: on a drive off Church Street before work, or in the car park at The King's Head on the way home. Unfamiliar motors come second, too. Hire cars, new vehicles and company vehicles put their fillers in new places, and the hand goes for the cap it used on the old one. And the bottle fits. A bottle with a spout goes into a diesel filler as easily as an AdBlue one, and so nothing stops the pour once it has started. Coleford or the heart of Highbury: it is the same few seconds either way. ## Telling the AdBlue filler from the diesel filler A couple of seconds is all these take — so run through them before you pour anything, on a driveway in Edford or a forecourt around Highbury. - The cap. The AdBlue cap is regularly blue, or marked "AdBlue". The diesel cap usually isn't. Read it instead of going by position. - The size. On plenty of cars the AdBlue filler neck is the smaller of the two. - A label inside your fuel flap often says which fuel goes where, on many vehicles. Look for it. - The handbook shows where it is when the filler isn't next to your diesel cap: the boot, or under the bonnet. - Collecting a hire or company car, say at the car park outside Frome? Check with whoever drove the car last before you set off, not once the light comes on. ## AdBlue top-ups that never reach your diesel tank On the day the warning comes on — wherever you are around Somerset — a routine to use. - Park then switch off. Not on a slope, not with the engine running, and not in a rush on the side of The Green. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds silly and it does the trick. - The diesel cap stays on. Where both sit under a flap, confirm it is shut before the bottle comes up. - Tip slowly, using the bottle's own spout. Stop when it's full or when the bottle is empty. - Only after that, start the car: close the cap, check again, and make sure the diesel cap was never opened. If at step two or three you find you have already poured into your diesel side, stop there. Step five stays off limits. ## Highbury: already put AdBlue in your diesel tank? Then the order of things is short. Do not start your motor. Keep the ignition off as well, since on many diesels switching it on by itself runs the fuel pump. AdBlue doesn't mix with diesel — it sinks to the bottom of your tank, where your fuel is pulled from — so do not top up with diesel to thin it. At a forecourt — Texaco, Shell or another — the staff will normally help roll the vehicle away, when you ask. Leave it where it is if you're on your own driveway in Highbury. Stop as soon as it is safe and switch off, if the engine has already run. Leave the M32 — under 25 miles out of Highbury — at the first junction. Tell us about how far it went: a run towards Wells, under 10 miles away, is a bigger job than a short hop across Highbury. ## Our arrival in Highbury, and what occurs next The van comes to your car anywhere it stopped — your own driveway, beside Coleford Aqueduct, or outside Bishop Henderson Church of England Primary School. Those replies decide the work and our quote, so we ask what got in, about how much, and if it's run. No one sets off until you have heard the price by phone. The fuel system is then cleaned thoroughly, after your tank is emptied. Unlike petrol, AdBlue leaves crystals and attacks some fuel-system metals, and none of that washes away unaided. Hence it counts more. The filter cleaned or, if it must be, replaced; clean diesel in; then a check of the car. Before we go, our engineers fire it up and make sure that it's running smoothly. If the engine has not run, most jobs take about half an hour once we're there, using pumps that are safe on a busy forecourt and quiet enough to use outside a house at night. You pay on the day, with nothing upfront, and get a VAT invoice and an engineer report for your insurer. Misfuelling cover is included in many insurance policies — and so use the wait to check yours. ## About Highbury itself Highbury is a small suburban area situated on the riverside in Somerset, with a mix of detached housing and rural scenery. Highbury sits at an elevation of around 125 metres, near the Mendip Hills and close to the nearby villages of Coleford and Ham. Highbury is located approximately 8.7 miles from the city of Wells, and its residents are around 101.9 miles from London. Highbury has a population of around 934 people, living in predominantly detached homes. ## AdBlue drains in Highbury and across Somerset Highbury is a residential suburb, and our vans that cover it also work the places around it, Ham and Leigh upon Mendip among them, across the BA postcode area. A postcode starting BA3 5 gets the van to you fastest. Moving the vehicle isn't needed. Wherever it sits — beside Holy Trinity Church, in a lay-by heading to Leigh Wood, at home — that is where it gets drained. Tricky to explain, like the back of The Royal British Legion? Close to a border? Checking beats guessing, and so phone. ## The short version for Highbury motorists Before you pour, read the cap. AdBlue in your diesel tank regardless? Keep it switched off then ring 0333 366 0103; Petrol in Diesel empties it where it stands, across Somerset.