--- title: AdBlue in a Diesel Tank Pool: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/pool-cornwall/ location: Pool county: Cornwall latitude: 50.227370 longitude: -5.268650 service: AdBlue in a Diesel Tank updated: 2026-10-04 --- # Preventing AdBlue in a Diesel Tank in Pool: Why It Happens Leave the engine and ignition off then phone 0333 366 0103 now — reading can wait if AdBlue is already in your diesel tank. A drain and a thorough flush, done right where the vehicle sits in Pool, is normally all it takes if caught before the motor runs. The rest of this page covers why it occurs and how to ensure it doesn't — handy if you're reading ahead of time. ## AdBlue in a diesel motor: two tanks, two fillers Not one liquid but two: that's how plenty of modern diesels around Pool and Tolskithy carry, with diesel feeding your engine. AdBlue goes to your exhaust, where it is sprayed into the gas to fresh it, and it lives in a tank of its own. Different tanks, separate fillers. Many of cars share a single flap for both, whereas others move the AdBlue filler to the boot or under the bonnet. The diesel side is fuelled at the petrol pump all the time. Someone who has to stop and work out where it goes normally tops up the AdBlue side, from a bottle, and far less often. It's in the gap that the slip happens. ## How AdBlue in the diesel tank happens in Pool Three things tend to come together, and carelessness is seldom one of them. The warning comes first. As AdBlue runs low the car tells you, and if it runs out completely, your vehicle drops into limp mode. So the top-up is done in a hurry: on a drive off Trevenson Road before work, or in the car park outside Plume of Feathers on the way home. The old car's filler is where your hand reaches — but a hire car, a new vehicle or a company car puts the fillers somewhere else. That's the second thing: a new motor. Nothing halts the tip once it has started, since a bottle with a spout goes into a diesel filler as readily as an AdBlue one. The bottle fits. It's a few seconds, be it in Penhallick or right in the heart of Pool. ## Which filler is for AdBlue, and which for diesel? Before you tip anything, whether on a driveway in Park Bottom or a forecourt around Pool, check these. They take a couple of seconds. - The cap. The AdBlue cap is commonly blue, or marked "AdBlue". The diesel cap normally isn't. Read it instead of going by where it sits. - Check the size: the smaller neck is, on plenty of vehicles, the AdBlue one. - A label inside the fuel flap often says which fuel goes where, on plenty of cars. Check for it. - Cannot find it next to your diesel filler? Then check below the bonnet or inside your boot — the owner's manual says which. - Picking up a hire or company car, perhaps at the car park at Camborne? Check with the person who drove the vehicle last before leaving, not when the light comes on. ## Keeping AdBlue out of the diesel tank when you top up When the light goes on, anywhere across Cornwall, follow this routine. - Stop somewhere level, motor off, with time to spare — not rushing on the side of Fore Street. - Locate the AdBlue filler, read the cap, and speak the name "AdBlue" aloud as unscrewing it. It sounds daft. It does the trick. - Both behind a single flap? Then confirm the cap on the diesel side is still closed before raising the bottle. - Gently is best, through the bottle's own spout, until it is full or the bottle runs out. - Shut the cap, and look again — confirm your diesel cap stayed shut throughout. Only then, start your car. Stop there if you find, at step two or three, that you've already poured into your diesel side. Leave out stage five entirely. ## Put AdBlue in the diesel tank in Pool already? Then the order of things is short. Do not start the engine. Don't switch the ignition on; on many diesels that alone runs the fuel pump. AdBlue does not mix with diesel — it sinks to the bottom of the tank, where your fuel is pulled from — so do not top up with diesel to dilute it. Ask the attendants to help push your car away from the pump if you are at a forecourt — the Morrisons, the Texaco or anywhere else. Leave it where it is if you are on your own driveway around Pool. Stop as soon as it is safe and switch off, if your motor has already run. The next junction is the place to come off if you're on the M5, over 50 miles from Pool. Mileage matters — a quick hop across Pool makes a smaller job than heading under 10 miles towards Truro — so tell us about how far it went. ## Pool: what occurs when our technicians arrive Our van comes to the vehicle wherever it has come to rest — your own drive, beside Cornish Diaspora, or by Treloweth Community Primary School. Which liquid got in, the quantity, and if it ran: our engineers ask since those answers decide the work and quote. On the phone call itself, you hear our quote — before anything else. Then the tank is emptied and the system cleaned thoroughly. More than with petrol, it matters here: the crystals build up, some metals are attacked, and nothing washes away unaided, no matter how long it sits. Your filter is cleaned, or replaced where it needs to be; fresh diesel goes in; and the vehicle is tested. The motor is started next and tested to confirm it runs correctly, all before our technicians leave. Unstarted cars usually need a half-hour job from arrival. The equipment is fine on a live filling station, and quiet enough for a driveway late at night. Your insurer usually wants an engineer's report and your VAT invoice, and you get both at the end. Payment is on the day, with no deposit. While we travel, have a look at your policy; many include cover for misfuelling. ## About Pool Pool is a village in Cornwall, situated near the coast and approximately 9.9 miles from Truro. Pool sits at an elevation of around 100 metres, overlooking the surrounding countryside. Pool is characterized by its predominantly detached housing stock, reflecting its residential nature. Pool is close to nearby places such as Penhallick and Illogan Highway. ## Pool and Cornwall: AdBlue drains across the area Illogan Highway and Tuckingmill are among the places near Pool, a coastal village, that the same teams cover, over TR postcodes. Our van reaches you fastest with a postcode starting TR15 3. The car doesn't need to move. The drain happens on the spot, be it a drive, a street near Pool Methodist Church, or a lay-by towards Trelowia. If you're near a border, or somewhere hard to describe like the back of 18th Century Chimney, ring and ask rather than guessing. ## Pool motorists: the short version Read the cap before you pour. If AdBlue has gone in the diesel tank anyway, leave the car off then ring 0333 366 0103. Petrol in Diesel drains it where it sits, anywhere in Cornwall.