--- title: Explained: AdBlue in a Diesel Tank Costhorpe canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/costhorpe-nottinghamshire/ location: Costhorpe county: Nottinghamshire latitude: 53.365540 longitude: -1.122410 service: AdBlue in a Diesel Tank updated: 2026-10-15 --- # Preventing AdBlue in a Diesel Tank in Costhorpe: Why It Occurs If AdBlue is already in your diesel tank, stop reading for a moment: leave your motor and the ignition off and phone 0333 366 0103. Usually, if the motor hasn't turned, it's emptied and thoroughly flushed where your vehicle sits around Costhorpe. Nothing happened yet? Below, the page explains the why it occurs and the ways to prevent it altogether. ## Two fillers, two tanks: AdBlue in a diesel motor Not one fluid but two: that's what plenty of newer diesels near Costhorpe and South Carlton carry, with diesel for your motor. AdBlue goes to the exhaust, where it is sprayed into the gas to fresh it, and it lives in a tank of its own. Every tank has one filler of its own. Some motors put the AdBlue filler in your boot or under the bonnet; plenty of others have the two side by side behind one flap. Diesel gets filled on each filling station call-out, week in, week out. Someone who has to stop and think where it goes usually fills the AdBlue side, from a bottle, and far less frequently. The mistake lives in that gap. ## Costhorpe: how AdBlue in your diesel tank takes place Three things tend to line up, and carelessness is seldom one of them. On a drive off Lawn Road before work, or in the car park at The Blue Bell heading home: that's where the rushed top-up happens. Why the rush? As AdBlue gets low the car warns you, and once it's empty, limp mode follows. New-to-you cars are second, too. Rentals, new vehicles and company vehicles place their fillers differently, and habit goes for the cap 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, so nothing stops the tip once it has started. The same few seconds settle it, in the middle of Costhorpe or out in Carlton in Lindrick. ## Which filler is for AdBlue, and which for diesel? A couple of seconds is all the checks take — so check them before you tip anything, on a drive in Wallingwells or a forecourt in Costhorpe. - Colour and lettering: an AdBlue cap is often blue, or says "AdBlue", where a diesel cap usually does not. Go by the cap, not where it sits. - On plenty of vehicles, the size tells: AdBlue gets the smaller filler neck. - A label inside the fuel flap frequently shows which fuel goes where, on plenty of motors. Look for it. - In your boot or under the bonnet: that is where the filler is if it is not by your diesel cap, and the handbook says which. - Collecting a hire or company car, perhaps at the car park at Shireoaks? Ask the person who drove it last before leaving, not once the light comes on. ## AdBlue top-ups that never reach the diesel tank For the day the warning comes on — anywhere it is in Nottinghamshire — a simple routine to use. - Not in a rush on the side of Northumberland Avenue, not on a slope, not with your engine running: park then switch off properly. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds silly and it does the trick. - If both sit under one flap, check the diesel cap is still closed before you lift the bottle — and leave it on. - Gently is best, through the bottle's own spout, until it's full or the bottle is empty. - Only after that, start your car: close the cap, check once more, and make sure the diesel cap was never opened. Spot at stage two or three that it's already gone into the diesel side? Then stop just there. Never go on to stage five. ## Costhorpe: already put AdBlue in the diesel tank? The short order of things, starting with not starting the motor. On many diesels your ignition alone runs the fuel pump, so do not switch the car on. AdBlue does not mix with diesel — it sinks to the bottom of the tank, where the fuel is drawn from — so do not top up with diesel to thin it. Ask the staff to help roll the car away from the petrol pump if you're at a forecourt — the Esso, the Tesco or anywhere else. Your own drive around Costhorpe is the place it should stay. When the motor has been run already, pull over somewhere safe and turn the car off. Costhorpe lies under 3 miles from the Doncaster By-Pass; there, use the first junction. Tell us roughly how far it went: a run towards Doncaster, under 15 miles away, is a bigger job than a short hop across Costhorpe. ## Costhorpe: what takes place when we get there Wherever the car has stopped, be it outside Kingston Park Academy, beside Carlton Youth Centre or at home, our van comes to it. Both the work and the quote rest on three answers — which liquid, what amount, and whether it's run — so our technicians ask. You get that quote on the phone, before anybody heads out. Next: draining, then a full flush of the whole system. Much more than with petrol, it counts with AdBlue: the crystals build up, certain metals are attacked, and none of that clears out on its own, however long it sits. Once the filter has been cleaned — or replaced, if required — clean diesel is added, and then the car is tested. Next our technicians fire it up and check it runs smoothly before we go. Most jobs are done in roughly half an hour after we arrive, provided the motor has not run — and the pumps our engineers use are fine on a live forecourt yet quiet after dark beside a house. Paying is on the day, not upfront, and you receive the paperwork an insurer wants: an engineer report and a VAT invoice. Plenty of insurance policies include misfuelling cover, and so it's worth checking yours while we are on the way. ## About Costhorpe itself Costhorpe is a suburban area in Nottinghamshire, situated inland at an elevation of 32 metres, and is located near several nearby places including Carlton in Lindrick, North Carlton, and Langold. Costhorpe has a population of approximately 1917 residents and features predominantly semi-detached housing. Costhorpe is also relatively close to the city of Doncaster, which is about 10.9 miles away. ## AdBlue drains across Nottinghamshire, Costhorpe included Over S postcodes, the teams that cover Costhorpe — a residential suburb — work the surrounding locations too, Langold and North Carlton among them. A postcode starting S81 9 gets our van to you fastest. Moving your car isn't needed. Our technicians drain it where it is — a side street near St Luke, a lay-by on the way to Costhorpe Plantation, a driveway. Assuming doesn't help at the back of Langold Library, on a border, or anywhere hard to describe; phone and check. ## The short version for Costhorpe people Before you pour, read the cap. Even so AdBlue in the diesel tank? Petrol in Diesel will drain it wherever it stands, anywhere in Nottinghamshire: switch the vehicle off and call 0333 366 0103.