--- title: AdBlue in a Diesel Tank Upper Siddington? Read This canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/upper-siddington-gloucestershire/ location: Upper Siddington county: Gloucestershire latitude: 51.696750 longitude: -1.957700 service: AdBlue in a Diesel Tank updated: 2026-10-10 --- # AdBlue in a Diesel Tank in Upper Siddington: How It Occurs and How to Stop It AdBlue already in your diesel tank? In that case put this page aside for now, keep the ignition and engine off, then ring 0333 366 0103. In Upper Siddington, catching it before your motor runs usually leaves draining and a thorough flush where it stands. The rest of this page explains why it occurs and how to ensure it does not — useful if you're reading before it has happened. ## AdBlue in a diesel motor, and its separate tank Many newer diesels around Preston, like those in Upper Siddington, run on two liquids; your engine gets only your diesel. Its own tank keeps it, and from there it is sent to your exhaust, and there a spray treats the fumes. Every tank comes with a filler of its own. On a lot of vehicles the two sit side by side under the same flap; on others the AdBlue filler is in your boot or under the bonnet. Filling the diesel side at the petrol pump happens all the time. Far less often, the AdBlue side gets topped up — mostly from a bottle, by someone thinking about where it goes. The error lives in that gap. ## How AdBlue in your diesel tank takes place in Upper Siddington Carelessness rarely explains it. Instead is three things lining up together. On a driveway off Upper Siddington before work, or in the car park at Greyhound on the way home: that is where the rushed top-up takes place. What is the reason for the rush? As AdBlue runs low the vehicle tells you, and once it's empty, limp mode follows. The old car's cap is where your hand goes — but a rental car, a new car or a company car keeps the fillers somewhere else. That is a second factor: a strange motor. A spout-topped bottle meets no resistance at a diesel filler any more than at an AdBlue one. So the pour, after begun, keeps on. Siddington or the middle of Upper Siddington: it is the same few seconds either way. ## Which filler is for AdBlue, and which for diesel? Check these before pouring, at a forecourt in Upper Siddington or a drive over in New Mills. A few seconds, no more. - The cap. The AdBlue cap is often blue, or marked "AdBlue". The diesel cap usually isn't. Read it instead of going by where it sits. - Plenty of vehicles give AdBlue the smaller neck of the two. - Lift the filler flap and look for a label — plenty of cars mark which belongs in each inlet right there. - In your boot or under the bonnet: that is where the filler is if it is not by the diesel cap, and the handbook tells you which. - Collecting a hire or company car, perhaps at the car park at Kemble? Ask the person who drove it last before you set off, not when the light goes on. ## How to top up without AdBlue in your diesel tank Anywhere across Gloucestershire the light comes on, here is a routine for the day. - Stop somewhere level, motor off, with time in hand — not rushing on the side of Pound Close. - Say "AdBlue" out loud as you unscrew the cap, once finding the AdBlue filler and read it. Silly, perhaps, but it works. - Both under a single flap? So make sure the lid on the diesel side is still closed before lifting the bottle. - Pour slowly, using the bottle's own spout. Stop when it is full or when the bottle is empty. - Only then, start your car: close the cap, check a second time, and make sure your diesel cap was never opened. Discover during the second or third stage that the bottle went into the wrong tank? That's where you stop. Stage five is off limits. ## Put AdBlue in the diesel tank in Upper Siddington already? Then the order of things is short. Do not start your motor. On plenty of diesels your ignition alone runs the fuel pump, and so do not switch the car on. Thinning it with more diesel won't work, since AdBlue settles to the base instead of mixing — and that is where your fuel is drawn from. If you're on a forecourt, whether it is the Tesco or the Esso, ask the staff to help roll your car away from the petrol pump. Your own drive in Upper Siddington is where it stays. When your engine has been run already, stop somewhere safe and turn it off. The next exit means the place to come off when you are on the M4, under 10 miles from Upper Siddington. A short hop across Upper Siddington is a smaller job than a run towards Gloucester, under 25 miles away, and so tell us roughly how far it went. ## What takes place when our technicians arrive around Upper Siddington Our engineers come to the vehicle wherever it has stopped, whether that's outside Siddington Church of England Primary School, near Saint Peter or on your own driveway. Which liquid went in, the amount, and if it ran: our engineers ask because those answers set the work and price. You hear that price by phone, before anybody heads out. Draining that tank comes next, followed by a full flush of the system. Much more than with petrol, it matters here: the crystals form, certain metals are attacked, and none of it washes away on its own, however long it is left. After your filter is cleaned — or renewed, where required — clean diesel is added, and finally your vehicle is tested. We don't leave until it has been started and is running smoothly. Most jobs are finished in roughly half an hour once our engineers get there, provided the motor has not run — and the pumps our technicians use are fine on a busy forecourt yet quiet after dark beside a house. Nothing upfront; you settle up that day. At the end, a VAT invoice and a report from the engineer are handed to you for the insurer. Many insurance policies include misfuelling cover, and so it's worth checking yours while we're on the way. ## About Upper Siddington, for a moment Upper Siddington is a village in Gloucestershire, situated on the riverside at an elevation of 112 metres, with semi-detached housing being the predominant type of accommodation. Upper Siddington lies near the villages of Siddington and Watermoor, and is approximately 16.9 miles from Gloucester. Upper Siddington has a population of around 788 residents, and is located in a scenic area of the South West region. Upper Siddington is also within commuting distance of larger cities, being around 79.6 miles from London. ## AdBlue drains in Upper Siddington and across Gloucestershire Upper Siddington is a village, and our teams that cover it also work the places near it, Watermoor and Kings Hill among them, across the GL postcode area. Quote a postcode beginning GL7 6, and the van gets there quickest. Moving your car is not necessary. The drain takes place right there, whether a drive, a street near Cirencester Baptist Church, or a lay-by towards Siddington Copse. Ring and ask instead of assuming if you're close to a boundary, or somewhere hard to describe, like the back of Hare Sculpture. ## In short, for Upper Siddington drivers Pour nothing till you have read the cap. Petrol in Diesel drains it on the spot, anywhere across Gloucestershire, if AdBlue has gone in the diesel tank regardless — so leave the car off then call 0333 366 0103.