--- title: Coisley Hill: AdBlue in a Diesel Tank, Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/coisley-hill-south-yorkshire/ location: Coisley Hill county: South Yorkshire latitude: 53.355760 longitude: -1.377960 service: AdBlue in a Diesel Tank updated: 2026-10-19 --- # Why It Happens and How to Avoid It: AdBlue in a Diesel Tank in Coisley Hill Pause here for a moment if your diesel tank already holds AdBlue in it: ignition off, motor off, then ring 0333 366 0103. Usually, if the engine hasn't turned, it's emptied and thoroughly purged where the vehicle is in Coisley Hill. Nothing happened yet? Below, the rest of the page covers the reasons it takes place and the how to avoid it altogether. ## AdBlue in a diesel motor, and its separate tank Not one fluid but two: that is how many newer diesels near Coisley Hill and Frecheville carry, with diesel for the motor. Kept in a tank of its own, AdBlue is sprayed into your exhaust gas to clean it. Separate tanks, separate fillers. Under one flap, next to each other: that's the layout on many vehicles. On others, AdBlue's filler sits under the bonnet or in your boot instead. Diesel goes in at every forecourt visit, week in, week out. Seldom topped up, AdBlue normally comes from a bottle, poured by a driver who has to stop and think what cap it needs. The mistake grows in that gap between them. ## How does AdBlue in your diesel tank take place in Coisley Hill? It is seldom carelessness. Three things tend to line up. On a drive off Water Slacks Drive before work, or in the car park outside The Angel on the way home: that's where the hurried top-up takes place. Why the rush? As AdBlue runs low your car tells you, and if it is gone, limp mode follows. Then the car is unfamiliar. A hire car, a new car or a company car puts the fillers where your last one didn't, and your hand hits for the cap it would have used on the old one. A spout-topped bottle finds no obstacle at a diesel filler any more than at an AdBlue one. And so the pour, once started, keeps on. The same few seconds settle it, in the middle of Coisley Hill or out in Woodhouse. ## The AdBlue filler and the diesel filler: telling them apart Look at these first, on a forecourt in Coisley Hill or a drive out in Owlthorpe. Seconds, no more. - Blue and marking: an AdBlue cap is often blue, or says "AdBlue", where a diesel cap normally does not. Trust the cap, not where it sits. - Plenty of vehicles fit AdBlue the smaller filler of the two. - A label inside your fuel flap frequently shows which fuel goes where, on many motors. Check for it. - Can't see it next to the diesel inlet? In that case look beneath the bonnet or inside the boot — the owner's manual says where. - Picking up a hire or company car, perhaps at the car park outside Woodhouse? Check with the person who drove the vehicle last before you set off, not once the light goes on. ## Keeping AdBlue out of your diesel tank when you top up On the day the light comes on — anywhere you are across South Yorkshire — a simple routine to follow. - Not in a rush on the side of Water Slacks Close, not on a slope, not with your 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 the two sit under a flap, confirm it's closed before the bottle comes up. - Using the bottle's own spout, pour slowly — and stop when it's full or the bottle is empty. - Before starting your car, shut the cap and look a second time that the diesel cap was never opened off. Find at step two or three that it has already gone into the diesel side? So stop just there. Leave out stage five altogether. ## Put AdBlue in your diesel tank in Coisley Hill already? Short list, then. First: your engine remains off. Leave your ignition off too, because on many diesels switching it on by itself starts your fuel pump. Topping up with diesel won't dilute it: instead, AdBlue sinks to the bottom of your tank, just where fuel is taken from. At a forecourt — Asda, another forecourt nearby or any other — the staff will normally help push the car away, if you ask. Your own drive in Coisley Hill is where it should stay. Where the engine has run already, pull over safely then turn it off. Leave the M1 — under 3 miles out of Coisley Hill — at the next exit. A short hop across Coisley Hill is a smaller job than a run towards Sheffield, under 5 miles away, and so tell us roughly how far it went. ## When our engineers arrive around Coisley Hill, what happens? We come to the vehicle wherever it has stopped, whether that is outside Woodhouse West Primary School, near Woodhouse Community Hub and Library or on your own driveway. The replies settle the work and the quote, so we ask what was put in, roughly how much, and whether it's run. That quote is given over the phone, ahead of any van leaving. Emptying the tank comes next, followed by a full flush of the fuel system. More than with petrol, it counts with AdBlue: crystals form, some metals are attacked, and nothing washes away on its own, no matter how long it is left. Testing is at the end: before that, clean diesel is added, and the fuel filter is flushed or replaced if necessary. Before we go, we fire it up and confirm that it is running properly. Unrun vehicles usually mean a half-hour visit after arrival. The kit is safe on a live forecourt, and quiet enough for a driveway after dark. Payment is on the day, not upfront, and you receive the paperwork an insurer asks for: an engineer report and a VAT invoice. It is worth looking at your insurance while we travel to you: misfuelling cover is included with plenty of policies. ## About Coisley Hill Coisley Hill is a locality situated near the River Don in South Yorkshire, with an elevation of around 92 metres. Coisley Hill lies close to the city of Sheffield, approximately 4.2 miles away, and is near other local places such as Woodhouse and Hackenthorpe. Coisley Hill is predominantly composed of flat housing, reflecting its urban character. Coisley Hill is located within a short distance from several local amenities and transport links. ## AdBlue drains across South Yorkshire, Coisley Hill included Throughout S postcodes, our vans that cover Coisley Hill — a small village — work the nearby locations too, Normanton Spring and Hackenthorpe among them. Give a postcode beginning S13 7, and our van arrives fastest. Your car does not need to shift. We drain it where it is — a side street close to The Salvation Army, a lay-by on the way to Shire Brook Valley, a driveway. Ring and ask rather than assuming if you are near a border, or somewhere hard to describe, like the back of Southern Light Community Church. ## In short, for Coisley Hill motorists First, the cap; after that, the tip. AdBlue in the diesel tank regardless? Keep it switched off then phone 0333 366 0103; Petrol in Diesel drains it on the spot, across South Yorkshire.