--- title: AdBlue in a Diesel Tank Graig Penllyn: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/graig-penllyn-the-vale-of-glamorgan/ location: Graig Penllyn county: The Vale of Glamorgan latitude: 51.488100 longitude: -3.475930 service: AdBlue in a Diesel Tank updated: 2026-10-21 --- # How It Occurs and How to Prevent It: AdBlue in a Diesel Tank in Graig Penllyn If AdBlue is already in your diesel tank, stop reading for a moment: leave your engine and your ignition off then phone 0333 366 0103. A drain and a thorough flush, carried out right where your car sits in Graig Penllyn, is normally all it needs when found before your motor runs. Here in advance? In that case the rest covers how it comes about and how to stop it ever happening. ## AdBlue in a diesel vehicle, and its separate tank Diesel goes to your motor — but many modern diesels seen about Graig Penllyn and Llansannor carry another liquid too. AdBlue goes to the exhaust, where it is sprayed into the gas to fresh it, and it lives in a tank of its own. There's a filler for every 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. At the pump, your diesel side gets filled constantly. Seldom filled, AdBlue normally comes out of a bottle, tipped by someone who has to stop and think what filler to use. It's in the gap that the mistake happens. ## AdBlue in your diesel tank in Graig Penllyn: how it occurs Seldom is it carelessness: usually three things coincide. On a drive off Salmons Wood before work, or in the car park outside The Barley Mow heading home: that's where the rushed top-up happens. What is the reason for the rush? As AdBlue gets low the car tells you, and if it's empty, limp mode kicks in. Then, your hand reaches for the cap it would have used on the old vehicle — because a rental car, a new vehicle or a company car puts the fillers where your last one did not. A spouted bottle finds no obstacle at a diesel filler any more than at an AdBlue one. So the tip, once started, carries on. The same few seconds settle it, in the middle of Graig Penllyn or out in Penllyn. ## The AdBlue filler and the diesel filler: telling them apart Look at these before pouring, at a forecourt around Graig Penllyn or a drive out in Pentre Meyrick. Seconds, no more. - Where it sits misleads; the cap does not. AdBlue caps are often blue or bear the name "AdBlue" — diesel caps usually do not. - Plenty of vehicles give AdBlue the smaller neck of the two. - Open the filler flap and check for a label — plenty of vehicles show which belongs in which inlet just there. - In your boot or under the bonnet: that is where your filler is if it's not by your diesel cap, and the handbook tells you which. - The previous driver will know. Ask when you collect a rental or fleet car — from Pencoed's car park, say — rather than once the warning comes on. ## Keeping AdBlue out of your diesel tank when you top up Wherever around The Vale of Glamorgan the light comes on, here is a routine for that day. - Park then switch off. Not on a slope, not with the engine running, and not in a rush on the side of Cae Rhedyn. - Say "AdBlue" out loud as you unscrew the cap, after finding the AdBlue filler and reading it. Silly, yes, yet it does the trick. - The diesel cap remains on. When both sit under a flap, confirm it is shut before the bottle comes up. - Tip slowly, using the bottle's own spout. Stop when it is full or when the bottle is empty. - Only then, start the vehicle: close the cap, check again, and make sure the diesel cap was never opened. Stop there if you find, at step two or three, that you've already poured into your diesel side. Step five stays off limits. ## Graig Penllyn: already put AdBlue in your diesel tank? The short order of things, starting with no starting your engine. The fuel pump runs on many diesels as soon as the ignition is switched on — and so leave it off. Filling up with diesel will not thin it: rather than mixing, AdBlue drops to the bottom of the tank, right where fuel is drawn from. Ask the staff to help push your car clear of the petrol pump if you're on a forecourt — the Texaco, the Murco or anywhere else. Leave it where it is if you are on your own driveway in Graig Penllyn. Already run? Pull over once it is safe, then turn off. On the M4, under 3 miles from Graig Penllyn, that means the next exit. Mileage counts — a short hop across Graig Penllyn makes a smaller job than heading under 15 miles to Cardiff — so tell us roughly how far it went. ## What happens when our technicians get there around Graig Penllyn Anywhere the vehicle came to rest, be it outside the local primary school, beside Church of St Mary the Virgin or on your own drive, the van travels to it. Both the work and our quote rest on three replies — which fluid, what quantity, and if it's run — so our engineers ask. The price comes on the call, ahead of any van leaving. Emptying the tank comes next, then a full flush of the system. With AdBlue that matters more than with petrol: it crystallises and is corrosive to some of the metals in a fuel system, so it does not wash out on its own. After your filter has been cleaned — or replaced, where required — clean diesel goes in, and finally the vehicle is tested. Before we leave, our technicians fire it up and confirm that it's running properly. Unrun vehicles usually need a half-hour visit after arrival. The equipment is safe on a busy forecourt, and quiet enough for a driveway after dark. The insurer will ask for an engineer's report and the VAT invoice, and both are yours once the job is done. Payment is on the day, with no deposit. It is worth checking your insurance as the van travels to you: misfuelling cover is included with many policies. ## About Graig Penllyn, for a moment Graig Penllyn is a small village in the Vale of Glamorgan, situated inland at an elevation of 56 metres. Graig Penllyn lies approximately 12.9 miles west of Cardiff and is surrounded by nearby villages such as Penllyn and St Mary Hill. Graig Penllyn has a population of around 542 people and predominantly features detached housing. Graig Penllyn is located in a rural area, with Llangan also nearby. ## AdBlue drains across The Vale of Glamorgan, Graig Penllyn included St Mary Hill and Llangan are among the towns around Graig Penllyn, a rural village, that the same teams cover, throughout CF postcodes. Quote a postcode beginning CF71 7, and the van arrives fastest. The car doesn't need to shift. The drain takes place on the spot, be it a drive, a street by Cowbridge Athletic Club, or a lay-by on the way to Coed y Graig. Ring and ask rather than assuming if you're close to a boundary, or somewhere hard to describe, like the back of Cowbridge United Free Church. ## The short version for Graig Penllyn people First, the cap; after that, the pour. AdBlue in your diesel tank regardless? Leave the car switched off then call 0333 366 0103; Petrol in Diesel empties it where it stands, across The Vale of Glamorgan.