--- title: Explained: AdBlue in a Diesel Tank Carn Brea Village canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/carn-brea-village-cornwall/ location: Carn Brea Village county: Cornwall latitude: 50.227130 longitude: -5.241810 service: AdBlue in a Diesel Tank updated: 2026-10-15 --- # Carn Brea Village: How Does AdBlue End Up in a Diesel Tank, and How Do You Prevent It? If AdBlue is already in your diesel tank, stop reading for a moment: leave your engine and your ignition off and phone 0333 366 0103. In Carn Brea Village, finding it before your engine turns usually means draining and a thorough flush where it stands. The remainder of this page explains why it takes place and how to make sure it doesn't — handy if you're reading ahead of time. ## Why does AdBlue in a diesel vehicle need its own filler? Plenty of newer diesels on the roads round Carn Brea Village and Church Coombe carry two liquids, not one. Diesel goes to the engine. The exhaust, not the engine, is where AdBlue ends up: sprayed into the fumes to clean them, from a separate tank. There's a filler on every tank. On a lot of vehicles the two sit side by side under the same flap; on others the AdBlue filler is in the boot or under the bonnet. Topping up the diesel side at the petrol pump happens constantly. A driver who has to stop and think where it goes normally tops up the AdBlue side, from a bottle, and far less frequently. The mistake grows in that gap between the two. ## AdBlue in the diesel tank around Carn Brea Village: how it takes place Seldom is it carelessness: normally three things line up. The warning comes first. As AdBlue runs low the car tells you, and if it runs out completely, your vehicle goes into limp mode. So the top-up is done in a hurry: on a drive off St Uny Crescent before work, or in the car park outside Rose Cottage on the way home. Next, your hand reaches for the cap it knew on the old motor — since a rental car, a new motor or a company car places the fillers somewhere your last one did not. And the bottle fits. A bottle with a spout goes into a diesel filler as easily as an AdBlue one, so nothing stops the pour once it has started. Church Town or the middle of Carn Brea Village: it takes the same few seconds either way. ## How to tell the AdBlue filler from the diesel one Before you tip anything, whether on a driveway in Illogan Highway or a forecourt in Carn Brea Village, check these. They take a couple of seconds. - Colour and marking: an AdBlue cap is often blue, or says "AdBlue", where a diesel cap normally doesn't. Go by the cap, not where it sits. - Many vehicles give AdBlue the smaller neck of the two. - The flap. Look inside the fuel flap for a label. Many cars say there which fuel goes where. - In your boot or under the bonnet: that's where your filler is if it's not by the diesel cap, and the handbook says which. - Collecting a hire or company car, say at the car park at Redruth? Ask the person who drove the car last before you set off, rather than once the light goes on. ## How to top up without AdBlue in your diesel tank Anywhere around Cornwall the light comes on, this is a routine for that day. - Not in a rush on the side of Blowinghouse Underbridge, not on a slope, not with your motor running: park then switch off properly. - Silly as it sounds, speaking "AdBlue" aloud while you unscrew the cap works — once you have found your filler and read it. - Both behind one flap? So confirm the lid on the diesel filler stays closed ahead of raising the bottle. - Gently is best, through the bottle's own spout, until it is full or the bottle is empty. - Before you start your car, shut the cap and check again that the diesel cap never came off. Find at step two or three that it has already gone into your diesel side? Then stop just there. Don't go on to stage five. ## Already put AdBlue in the diesel tank in Carn Brea Village? Don't start your motor: that is where the short order of things begins. On plenty of diesels your ignition alone runs the fuel pump, so do not switch the car on. Filling up with diesel won't dilute it: rather than mixing, AdBlue drops to the bottom of the tank, right where fuel is drawn from. At a forecourt — Texaco, Tesco or any other — the staff will usually help push the vehicle away, if you ask. On your own drive around Carn Brea Village? So the vehicle remains put. If your engine has already run, stop as soon as it is safe and switch off. On the M5, over 50 miles from Carn Brea Village, that means the next junction. Tell us roughly how far it went: a run towards Truro, under 10 miles away, is a bigger job than a short hop across Carn Brea Village. ## Carn Brea Village: what takes place when our engineers turn up Our technicians come to your car wherever it has stopped, whether that's outside Trewirgie Infants' School, near Carn Brea Village Hall or on your own drive. The replies determine the work and the price, and so our technicians ask what was put in, roughly how much, and if it has run. The quote is given on the call, ahead of any van leaving. After that: draining, then a thorough flush of the whole system. AdBlue crystallises and is corrosive to some of the metals in a fuel system, so it doesn't wash out on its own — which is why that matters more here than with petrol. A test comes last: before that, fresh diesel goes in, and your filter is cleaned or replaced as needed. The motor is started next and tested to make sure it runs properly, all before our engineers leave. Unrun cars mostly mean a half-hour job after arrival. The equipment is fine on a busy filling station, and quiet enough for a residential street after dark. You pay on the day, with nothing upfront, and get a VAT invoice and an engineer report for your insurer. Before we get there, have a look at your policy; plenty include cover for misfuelling. ## About Carn Brea Village and where it is Carn Brea Village is a small settlement in inland Cornwall, situated near the town of Truro and the villages of Church Town and Blowinghouse. Carn Brea Village sits at an elevation of 109 metres, surrounded by the rolling countryside of the South West region. Carn Brea Village has a population of around 1234 people, predominantly living in detached houses. ## AdBlue drains around Carn Brea Village, and Cornwall beyond Over TR postcodes, our teams that cover Carn Brea Village — a rural village — work the nearby places too, Tolskithy and Blowinghouse included. The van gets to you fastest with a postcode starting TR15 3. The vehicle stays put. Anywhere it stands — beside St Euny Parish Church, in a lay-by en route to The Fairfield, at home — that is where it is cleared. Assuming won't help behind Carn Brea Castle, on a border, or somewhere hard to describe; phone and check. ## For Carn Brea Village people, the short version Pour nothing till you have read the cap. Petrol in Diesel empties it on the spot, anywhere across Cornwall, if AdBlue has gone in the diesel tank anyway — and so leave it off then ring 0333 366 0103.