--- title: AdBlue in a Diesel Tank St Leonards: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/st-leonards-city-of-edinburgh/ location: St Leonards county: City of Edinburgh latitude: 55.939780 longitude: -3.173530 service: AdBlue in a Diesel Tank updated: 2026-10-21 --- # Why It Happens and How to Avoid It: AdBlue in a Diesel Tank in St Leonards Keep your engine and ignition off and phone 0333 366 0103 first — the rest can wait when AdBlue is already in your diesel tank. A drain and a full flush, carried out just where the car sits around St Leonards, is usually what it takes if caught before the motor runs. Not happened yet? Further down, the page explains the reasons it happens and the how to prevent it for good. ## AdBlue in a diesel car: two tanks, two fillers Many newer diesels around Newington, like those in St Leonards, carry on two liquids; your engine gets just the diesel. AdBlue's own tank holds it, and from there it goes to the exhaust, where a spray cleans the gas. Each tank has its own filler. Other vehicles put the AdBlue filler in your boot or under the bonnet; a lot of others have both together under one flap. Diesel goes in on every forecourt call-out, again and again. Someone who has to stop and think where it goes usually fills the AdBlue side, from a bottle, and far less often. The slip lives in that gap. ## How AdBlue in the diesel tank occurs in St Leonards It is seldom carelessness. Three things tend to line up. Hurry follows from the warning. The car tells you as AdBlue runs low, and a dry tank puts the vehicle into limp mode — so the top-up gets done in a rush, before work on a drive off Holyrood Park Road, or on the way home in the car park at The Salisbury Arms. Next, your hand reaches for the cap it would have used on the old vehicle — because a hire car, a new vehicle or a company car places the fillers somewhere your last one didn't. Lastly, the spout fits: a diesel filler or AdBlue filler, it slides in just as easily, and once the pour begins, nothing halts it. Dumbiedykes or the middle of St Leonards: it is the same few seconds either way. ## Which filler is for AdBlue, and which for diesel? A few seconds is all the checks take — so check them before you tip anything, on a drive in Grange Park or a forecourt in St Leonards. - Colour and lettering: an AdBlue cap is frequently blue, or says "AdBlue", where a diesel cap normally doesn't. Trust the cap, not where it sits. - Many vehicles give AdBlue the smaller filler of the two. - Check inside your fuel flap: plenty of vehicles carry a label there showing which fuel goes where. - The handbook says which it is if the filler isn't next to the diesel cap: the boot, or under the bonnet. - Picking up a hire or company car, perhaps at the car park outside Edinburgh Waverley? Ask the person who drove it last before you set off, rather than once the light comes on. ## How to top up without AdBlue in your diesel tank A routine for the day the light comes on, wherever around City of Edinburgh that is. - Switch off once parked — level ground, engine stopped, and never rushed by Dalkeith Road at the roadside. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds daft and it works. - If both sit under one flap, check your diesel cap is still closed before you lift the bottle — then leave it on. - Using the bottle's own spout, tip slowly — and stop when it's full or the bottle is empty. - Close the cap and check a second time. Make sure the diesel cap was never opened. Only then start the car. Spot at stage two or three that it has already gone into your diesel side? Then stop just there. Stage five is off limits. ## Already put AdBlue in the diesel tank in St Leonards? What follows is a short order of things, starting with no starting your engine. Keep the ignition off as well, because on plenty of diesels switching it on alone runs the pump. Don't top up with diesel to thin it: AdBlue doesn't mix with diesel, it sinks to the bottom of the tank, where the fuel is sucked from. If you are on a forecourt, whether it is the BP or the Sainsbury's, ask the attendants to help push your car away from the petrol pump. Leave it where it is if you're on your own drive in St Leonards. When the motor has run by now, pull over safely and turn it off. St Leonards sits under 10 miles from the M8; there, use the first exit. About how far did it go? Crossing St Leonards is less work than a trip of under 3 miles towards Edinburgh, and so say. ## What happens when our technicians turn up around St Leonards By the local primary school, near Royal Commonwealth Pool or on your own drive: wherever the car has stopped, our technicians come to it. Which liquid went in, the amount, and if it ran: our technicians ask since the replies decide the work and quote. No one sets off before you've had our quote by phone. After that: draining, then a full flush of the entire system. Much more than with petrol, it matters with AdBlue: the 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 car is tested. We do not go until it has been started and is running smoothly. Unrun vehicles usually mean a half-hour job after the moment we arrive. The kit is fine on a live filling station, and hushed enough for a driveway late at night. The 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 money upfront. Wrong-fuel cover is included in many insurance policies — so make use of the wait to look at yours. ## About St Leonards, briefly St Leonards is a suburban area in the City of Edinburgh, situated near the coast and approximately 1.1 miles from Edinburgh city centre. St Leonards sits at an elevation of around 89 metres, overlooking the surrounding landscape. St Leonards is predominantly composed of flat-type housing, which accommodates its population of around 13401 residents. St Leonards is close to nearby places such as Dumbiedykes, South Side, and Sciennes. ## AdBlue drains across City of Edinburgh, St Leonards included As a residential suburb, St Leonards has the same vans as surrounding areas — South Side, Sciennes — all the way through EH postcodes and the surrounding area around them. A postcode starting EH16 5 gets our van to you fastest. There's no need to move your car. Draining happens right there, whether a drive, a street near Thomas Nelson Publishers War Memorial, or a layby towards Priestfield Tennis and Sports Association. If you're near a boundary, or somewhere hard to explain like the back of Salisbury Centre, ring and ask rather than assuming. ## For St Leonards drivers, the short version First, the cap; then, the pour. AdBlue in your diesel tank regardless? Leave the vehicle switched off and call 0333 366 0103; Petrol in Diesel empties it on the spot, across City of Edinburgh.