--- title: Old Town: AdBlue in a Diesel Tank, Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/old-town-city-of-edinburgh/ location: Old Town county: City of Edinburgh latitude: 55.949060 longitude: -3.194390 service: AdBlue in a Diesel Tank updated: 2026-10-28 --- # Preventing AdBlue in a Diesel Tank in Old Town: Why It Occurs AdBlue already in your diesel tank? In that case put this page down a moment, leave the ignition and engine off, then call 0333 366 0103. Usually, if your motor has not run, it is emptied and thoroughly flushed where your car sits around Old Town. If you're reading before it has happened, the rest of this page is about why it takes place and how to make sure it doesn't. ## AdBlue in a diesel motor, and its separate tank Many modern diesels on the roads about Old Town and South Side carry two liquids, not one. Diesel goes to your engine. Its own tank holds it, and from there it is sent to the exhaust, and there a spray treats the gas. There's a filler for each tank. On a lot of cars the two sit side by side under the same flap; on others the AdBlue filler is in your boot or under the bonnet. Topping up the diesel side at the petrol pump goes on constantly. A driver who has to stop and work out where it goes normally fills the AdBlue side, from a bottle, and much less often. That gap is where the slip lives. ## How does AdBlue in your diesel tank occur around Old Town? Seldom is it carelessness: normally three things coincide. The warning comes first. As AdBlue runs low the vehicle tells you, and if it runs out completely, the car drops into limp mode. So the top-up is done in a hurry: on a drive off Castlehill before work, or in the car park outside Ensign Ewart on the way home. Then the vehicle is new. A hire car, a new car or a company car puts the fillers where your last one did not, and the hand reaches for the cap it would have 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 tip after it has started. The same few seconds settle it, in the middle of Old Town or out in Roxburghs Court. ## Telling the AdBlue filler from your diesel filler A couple of seconds is all these take — so check them before you pour anything, on a driveway in Tollcross or a forecourt in Old Town. - Check the cap rather than going by where it sits: AdBlue caps are often blue or marked "AdBlue", and diesel ones normally are not. - On many cars, the size gives it away: AdBlue has the smaller filler neck. - A label inside the fuel flap frequently says which fuel goes where, on plenty of vehicles. Check for it. - In the boot or under the bonnet: that's where the filler sits if it's not by the diesel cap, and the handbook tells you which. - Collecting a hire or company car, say at the car park at Edinburgh Waverley? Ask the person who drove it last before you set off, not once the light comes on. ## AdBlue top-ups that never reach your diesel tank The day the light comes on, wherever in City of Edinburgh, follow this routine. - Not in a rush on the side of Johnston Terrace, not on a slope, not with the 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 daft and it does the trick. - The diesel cap remains on. When both share a flap, confirm it is shut before the bottle comes up. - Pour slowly, using the bottle's own spout. Stop when it is full or when the bottle is empty. - Before starting your car, close the cap and look a second time that the diesel cap was never opened off. Discover during the second or third stage that AdBlue went in the wrong tank? That's where you stop. Never carry on to step five. ## AdBlue in the diesel tank already, in Old Town? Then the order of things is short. Don't start your motor. The fuel pump runs on many diesels as soon as your ignition goes on — so keep it off. Topping up with diesel will not weaken it: instead, AdBlue sinks to the base of your tank, right where fuel is drawn from. Ask the staff to help roll the car away from the pump if you are at a forecourt — the JET, the BP or somewhere else. Leave it where it is if you're on your own drive in Old Town. Stop as soon as it is safe and switch off, if the motor has already run. Old Town sits under 5 miles from the M8; there, take the first junction. About how far did it go? Crossing Old Town is less a job than a run of under a mile towards Edinburgh, and so tell us. ## What happens when our technicians arrive in Old Town Anywhere the vehicle came to rest, be it outside the local primary school, beside Sir Rudolph Bing or on your own drive, our van comes to it. Our engineers ask what got in, roughly how much, and if it's run, because the answers decide this work and our price. That quote is given over the phone, ahead of any van leaving. Then your tank is emptied and the fuel system cleaned thoroughly. Much more than with petrol, it counts with AdBlue: crystals form, some metals corrode, and nothing washes out unaided, however long it sits. Your filter is cleaned, or replaced where it needs to be; clean diesel goes in; and the vehicle is tested. The motor is fired up next and tested to be sure it runs correctly, all before our technicians head off. With pumps safe on a busy forecourt and quiet enough for use outside a house at night, most jobs where your motor has not run take about half an hour once we are there. No money in advance; you settle up that day. At the end, the VAT invoice and the report from the engineer go to you for the insurer. Many insurance policies include misfuelling cover, so it is worth checking yours whilst we are on the way. ## About Old Town itself Old Town is a historic suburban area in the City of Edinburgh, situated on the southern shore of the Firth of Forth, with the city centre nearby. Old Town sits at an elevation of around 99 metres, overlooking the coastal scenery of the Firth of Forth. Old Town is characterized by its predominantly flat-type housing, which reflects the area's urban development. Old Town is closely linked to neighbouring areas such as Roxburghs Court and New Town, with Edinburgh city centre just 0.4 miles away. ## AdBlue drains in Old Town and across City of Edinburgh Old Town is a residential suburb, and our vans that cover it also work the places near it, New Town and Edinburgh among them, across the EH postcode area. Give a postcode that starts EH1 2, and our van gets there quickest. The car stays where it is. Anywhere it stands — beside General Assembly Hall, in a lay-by heading to Quiet Garden, on a drive — that's where it gets cleared. Awkward to pin down, like the back of St Columba's Free Church? Close to a border? Checking beats guessing, so ring. ## In short, for Old Town drivers Pour nothing till you've read the cap. Even so AdBlue in the diesel tank? Petrol in Diesel can empty it where it is, wherever around City of Edinburgh: keep the car off then phone 0333 366 0103.