--- title: Explained: AdBlue in a Diesel Tank Southwood canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/southwood-hampshire/ location: Southwood county: Hampshire latitude: 51.291510 longitude: -0.783530 service: AdBlue in a Diesel Tank updated: 2026-10-15 --- # Southwood: How Does AdBlue End Up in a Diesel Tank, and How Do You Avoid It? Keep the motor and ignition off and ring 0333 366 0103 now — the rest can wait if AdBlue is already in your diesel tank. In Southwood, catching it before your engine runs usually means a drain and a full flush on the spot. Not happened yet? Below, the page covers the reasons it takes place and the how to prevent it for good. ## Two fillers, two tanks: AdBlue in a diesel motor Diesel goes to the engine — yet many current diesels driven around Southwood and Farnborough carry another fluid as well. AdBlue's own tank keeps it, and from there it is sent to the exhaust, where a spray cleans the gas. Separate tanks, different fillers. Other cars put the AdBlue filler in your boot or under the bonnet; plenty more place both side by side under one flap. Filling the diesel side at the petrol pump goes on all the time. A driver who has to stop and work out where it goes usually tops up the AdBlue side, from a bottle, and much less frequently. It's in the gap that the slip happens. ## Southwood: how AdBlue in the diesel tank occurs It's hardly ever carelessness. Three things tend to line up. On a drive off Southwood Road before work, or in the car park at The Sarsen Stones on the way home: that's where the rushed top-up happens. Why the rush? As AdBlue runs low the car tells you, and once it is gone, limp mode kicks in. The old car's filler is where the hand reaches — but a hire car, a new motor or a company car puts the fillers somewhere else. That is a second factor: an unfamiliar vehicle. Nothing stops the tip after it has started, because a bottle with a spout goes into a diesel filler as easily as an AdBlue one. The bottle fits. Whether it happens in Cove or the middle of Southwood, it's the same few seconds. ## Which filler is for AdBlue, and which for diesel? Before you pour anything, whether on a driveway in Fox Lane or a forecourt in Southwood, check these. They take a few seconds. - Position can mislead; the cap doesn't. AdBlue caps are often blue or bear the name "AdBlue" — diesel caps usually don't. - Look at the size: the smaller filler neck is, on plenty of vehicles, the AdBlue one. - Lift the filler flap and look for a label — plenty of vehicles mark what goes in each inlet right there. - Can't find it beside your diesel filler? Then check below the bonnet or inside your boot — the owner's manual will say where. - The previous driver will know. Check when you pick up a hire car or company car — from Farnborough Main's car park, say — not when the light appears. ## AdBlue top-ups that never reach the diesel tank Wherever in Hampshire the light comes on, this is a routine for that day. - Not in a rush on the side of Ively Road, not on a slope, not with your engine running: park and switch off first. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds silly and it works. - If both sit under one flap, check your diesel cap is still closed before you lift the bottle — then leave the vehicle on. - Using the bottle's own spout, tip slowly — and stop when it's full or the bottle is empty. - Shut the cap, and check once more — confirm the diesel cap stayed closed the whole time. Only then, start your car. Spot at stage two or three that it's already gone into the diesel side? Then stop right there. Never go on to stage five. ## Southwood: already put AdBlue in the diesel tank? Short order, then. Top of that: your engine stays unstarted. Keep your ignition off too, since on plenty of diesels switching it on by itself starts your fuel pump. Topping up with diesel won't weaken it: rather than mixing, AdBlue drops to the bottom of that tank, just where the fuel is taken from. At a forecourt — Morrisons, Esso or another — the staff will normally help push the vehicle clear, if you ask. Your own drive around Southwood is the place it stays. Already started? Pull over when it is safe, then turn off. On the M3, under a mile from Southwood, that means the next exit. Tell us about how far it went: a run towards Winchester, under 50 miles away, is a bigger job than a short hop across Southwood. ## When our engineers arrive in Southwood, what happens? By Southwood Infant School, close to St John the Baptist or on your own driveway: wherever your car has stopped, our technicians come to it. Our technicians ask what was put in, roughly how much, and if it has run, because those answers settle the work and our price. Nobody heads out before you have had our quote over the phone. Then your tank is cleared and the system purged thoroughly. Not like petrol, AdBlue forms crystals and eats at some fuel-system metals, and none of that clears out unaided. Hence it counts more. Filter flushed or, where it must be, swapped; clean diesel in; and then a test of your vehicle. The motor is fired up next and checked to be sure it runs properly, all before we go. Most jobs are finished in about half an hour once our engineers get there, provided your engine hasn't run — and the pumps our engineers use are fine on a busy forecourt and quiet after dark beside a house. Your insurer will ask for an engineer's report and the VAT invoice, and you get both once the job is done. Payment comes on the day, with no deposit. Before we get there, take a look at your policy; plenty include cover for misfuelling. ## About Southwood Southwood is a suburban area in Hampshire, situated on the riverside with an elevation of 67 metres. Southwood lies within the South East region of England, approximately 32 miles from London and 28 miles from the city of Winchester. Southwood is characterised by its predominantly detached housing stock and is surrounded by nearby places such as Cove, West Heath, and Rafborough. Southwood has a population of around 4523 residents. ## AdBlue drains across Hampshire, Southwood included Over GU postcodes, our vans covering Southwood — a residential suburb — work the nearby spots too, Rafborough and West Heath included. Quote a postcode that starts GU14 0, and our van gets there fastest. The car doesn't need to shift. A driveway, a lay-by on the way to Southwood Playing Fields, a side street near Sir Frank Whittle: our technicians drain the car where it is. Assuming doesn't help at the back of St Christopher, on a border, or somewhere hard to describe; phone and ask. ## The short version for Southwood people Tip no AdBlue until you've read the cap. Still AdBlue in your diesel tank? Petrol in Diesel will drain it where it stands, wherever across Hampshire: switch the vehicle off and ring 0333 366 0103.