--- title: AdBlue in a Diesel Tank Penrhyn-side: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/penrhyn-side-conwy/ location: Penrhyn-side county: Conwy latitude: 53.318460 longitude: -3.781560 service: AdBlue in a Diesel Tank updated: 2026-10-20 --- # How It Occurs and How to Prevent It: AdBlue in a Diesel Tank in Penrhyn-side If AdBlue is already in your diesel tank, stop reading for a moment: leave the engine and the ignition off then ring 0333 366 0103. Caught before the motor runs, it is generally a drain and a thorough flush, done where the vehicle is in Penrhyn-side. Nothing happened yet? Below, the rest of the page covers the reasons it occurs and the ways to prevent it altogether. ## Two fillers, two tanks: AdBlue in a diesel vehicle Many current diesels on the roads around Penrhyn-side and Llangwstenin carry two liquids, not one. Diesel goes to your engine. AdBlue's own tank holds it, and from there it is sent to your exhaust, and there a spray treats the fumes. Each tank comes with a filler of its own. Under one flap, next to each other: that's the arrangement on many cars. On others, AdBlue's filler is under the bonnet or in the boot instead. Diesel gets filled on each forecourt call-out, again and again. Much less regularly, the AdBlue side is topped up — normally from a bottle, by a person thinking about where it goes. Mistakes happen in the gap between the two. ## How AdBlue in the diesel tank happens around Penrhyn-side It is rarely carelessness. Three things tend to line up. On a driveway off Pen y Parc before work, or in the car park at Penrhyn Arms 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 gone, limp mode follows. Then, the hand reaches for the cap it knew on the old car — since a hire car, a new vehicle or a company car puts the fillers somewhere your last one did not. No part stops the tip once it has started, because a bottle with a spout goes into a diesel filler as easily as an AdBlue one. The bottle fits. Whether it takes place in Penrhyn Bay or the middle of Penrhyn-side, it is the same few seconds. ## How to tell the AdBlue filler from the diesel one Be it a Penrhyn-side forecourt or a drive over in Llandrillo-yn-Rhos, take a couple of seconds over these before anything is poured in. - Position can mislead; the cap doesn't. AdBlue ones tend to be blue or bear the word "AdBlue" — diesel ones normally don't. - The size. On many cars the AdBlue filler neck is the smaller of the two. - Check inside the fuel flap: many motors have a label there saying which fuel goes where. - Cannot see it next to the diesel inlet? Then check below the bonnet or in the boot — the handbook will say which. - Collecting a hire or company car, perhaps at the car park at Llandudno? Ask whoever drove the car last before you set off, rather than when the light goes on. ## Topping up AdBlue without it reaching the diesel tank Anywhere in Conwy the light comes on, this is a routine for the day. - Not in a rush on the side of Bryn Gwynt Lane, not on a slope, not with the engine running: park then switch off properly. - Locate the AdBlue filler, read the cap, and say the name "AdBlue" out loud while unscrewing it. It seems daft. It works. - If both sit under one flap, check the diesel cap is still closed before you lift the bottle — then leave it on. - Pour slowly, using the bottle's own spout. Stop when it's full or when the bottle is empty. - Only after that, start your car: close the cap, check once more, and make sure the diesel cap was never opened. Stop there if you find, at stage two or three, that you've already poured into your diesel side. Don't go on to stage five. ## Already put AdBlue in the diesel tank in Penrhyn-side? What follows is a short order of things, beginning with no starting the motor. The fuel pump starts on plenty of diesels the moment your ignition goes on — so keep it off. Thinning it with extra diesel fails, since AdBlue settles to the bottom rather than blending — and that's where your fuel is sucked from. If you're at a forecourt, whether it is the Gulf or the JET, ask the attendants to help push the vehicle clear of the pump. Leave it where it is if you are on your own driveway in Penrhyn-side. Already run? Stop once it's safe, then turn off. The next exit is where to come off when you are on the Moreton Spur, under 50 miles from Penrhyn-side. About how far did it go? Hopping across Penrhyn-side is less a job than a run of under 15 miles towards St Asaph, so say. ## Our arrival around Penrhyn-side, and what occurs next Our van comes to the vehicle anywhere it has come to rest — your own driveway, beside Village Hall, or outside the local primary school. What fluid got in, the amount, and if it ran: we ask because those answers set both work and price. You hear that price by phone, before anybody heads out. The fuel system is then purged thoroughly, once the tank is drained. AdBlue crystallises and is corrosive to some of the metals in a fuel system, so it does not wash out on its own — which is why the flush matters more with AdBlue than with petrol. After the fuel filter has been flushed — or replaced, if needed — clean diesel is added, and finally your vehicle is tested. After that our technicians fire it up and check it runs correctly before we go. Unstarted cars usually mean a half-hour job from the moment we arrive. The equipment is fine on a busy filling station, and hushed enough for a driveway late at night. Payment happens on the day, not upfront, and you receive the documents an insurer wants: an engineer report and a VAT invoice. While we travel, have a look at your insurance documents; many carry cover for misfuelling. ## About Penrhyn-side itself Penrhyn-side is a coastal village in Conwy, situated near the popular seaside resort of Penrhyn Bay. Penrhyn-side has a mix of semi-detached housing and is located at an elevation of 77 metres, with views out to the Irish Sea. Penrhyn-side is close to the nearby villages of Glanwydden and Craig-y-Don, and is within commuting distance of the city of St Asaph. ## Penrhyn-side and Conwy: AdBlue drains across the area Over LL postcodes, our vans covering Penrhyn-side — a coastal village — work the nearby spots too, Craig-y-Don and Glanwydden among them. Fastest of all: give a LL30 3 postcode for our van. The vehicle remains where it is. Wherever it sits — near Addoldy Y Bedyddwyr, on a lay-by heading to Rhiwledyn Nature Reserve, at home — that is where it is emptied. Ring and ask instead of guessing if you are near a border, or somewhere hard to describe, like the back of Jen Art. ## Penrhyn-side people: the short version First, the cap; after that, the pour. Even so AdBlue in the diesel tank? Petrol in Diesel can drain it where it stands, wherever around Conwy: keep the vehicle off then phone 0333 366 0103.