--- title: Don't Start It: AdBlue in a Diesel Tank Lanner canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/lanner-cornwall/ location: Lanner county: Cornwall latitude: 50.215600 longitude: -5.200440 service: AdBlue in a Diesel Tank updated: 2026-10-25 --- # AdBlue in the Diesel Tank in Lanner? Keep It Switched Off Motor off, ignition off: that's where you start if AdBlue has got into your diesel tank. In plain terms, AdBlue is simply urea in water. It does not burn, it doesn't mix with diesel, and the harm it does begins when the fuel system pulls it in. A drain and a thorough flush, done where the vehicle is in Lanner, is usually all AdBlue in a diesel tank needs — if it's caught before the engine has been run. Nothing comes before calling 0333 366 0103. ## AdBlue in the diesel tank in Lanner: the first few minutes Do these: - Keys out — that way nobody can switch anything on. - Near moving traffic? Then put the hazard lights on. - The empty bottle or the receipt shows us the product and the amount, so don't bin it away. - Ring just where you are. Say a TR16 6 postcode or the nearest street sign, and nobody has to search for you. Don't do these: - Shifting the car even a short way is no reason to start your motor. - Many diesels power their pump the moment your ignition goes on, and so leave the car off. - Don't top up with diesel to dilute it. AdBlue doesn't dilute in diesel; it separates out. - Do not drive the vehicle anywhere, not even a short way up Lanner Hill. - Draining the tank on your own beside the road is not one to try. Moving the vehicle off the island is a job for attendants to help with, whichever Lanner forecourt you're on, the Shell or any other. If you're on your own drive, leave it just where it is. ## What does AdBlue do in a diesel tank? Meant for the exhaust, AdBlue has no place in the engine. It goes into its own tank and is sprayed into your exhaust gas to clean it. A fuel pump is not designed to cope with it, and AdBlue was never intended to go through one. Inside a diesel tank it acts really differently from fuel. It doesn't mix in. Denser than diesel, it sinks and pools below it — the very spot the intake draws from. The first thing the system pulls through, after it runs, is the AdBlue. So a vehicle that had AdBlue poured in on a drive in Trevarth last night, and hasn't been started since, is still the straightforward case: the AdBlue is lying at the bottom of the tank, and nothing has drawn it in. Two kinds of damage follow from there. What is left when the water goes is urea, which forms crystals: they settle in tiny channels and clog filters. On top of that, it attacks certain metals in the fuel system, and carries on until it is flushed out. A motor left sitting in Lanner with AdBlue already in its lines is worse by the morning; one with AdBlue only in its tank is not. And there's the water: it offers no protection to the components that rely on it most — the injection pump and each injector. ## Petrol or AdBlue in a diesel: why AdBlue is often worse Top up a diesel with petrol in error at the Opie Oils, and the problem is diluted fuel. Blended into the diesel and left still, it is no threat for now; running your motor does the harm. AdBlue in a diesel is a different problem: not thin fuel, but no fuel at all. Not burning, it can't simply be run through. It does not stay mixed, and so it cannot be diluted. And crystals and corrosion don't wash out with the next tank of fuel. That's why the flush matters more with AdBlue than with petrol, and why starting your motor "to see" costs more here than nearly anywhere else, whether the car is in Trethellan Water or the middle of Lanner. The good news is the same as with petrol. Emptying a tank is the easiest job on a fuel system, and with no running, the AdBlue remains in there — anywhere in Cornwall your vehicle sits. ## Lanner: how AdBlue ends up in a diesel tank Plenty of vehicles put the AdBlue filler beside the diesel cap, now and then behind a single flap, and after dark the two may look the same. Nobody means it. A bottle picked up while heading home and tipped in outside the house, rather than at the filling station, is the typical route. It tends to occur in a few familiar ways. Halfway through the morning drop-off, the dashboard warns, and outside Lanner Primary School the top-up is hurried. Someone pours the bottle in at home, right off Penmayne Parc, as the day ends. Else, in dim light outside Lanner Inn, the vehicle gets refilled by a driver opening that flap the first time. It comes up the most in a rental, a brand-new motor, a company car, or the spare car in a home with both fuel types — the vehicles people use least. Wherever you're around Lanner or the remainder of Cornwall, it's the same mistake and the same first answer: leave it off. ## AdBlue in the diesel tank in Lanner, and the motor started? The AdBlue has left the tank, then. Your filter and lines have had it sucked along, and any running takes it on to the injection pump and every injector. Maybe returning from Lanner Moor Recreation Ground, or midway across Lanner, your engine might run rough, smoke, lose power, flash your dash or stall. Pull over when it is safe. Turn off. Keep it off instead of testing it again. More of it is pulled through with each start. On the M5, over 50 miles from Lanner, the first junction is where to leave, and anywhere sensible is where to stop — not carrying on. How far it went counts. A couple of hundred yards across Lanner to the car park by Lanner Methodist Church is a very different job from a run towards Truro, under 10 miles away, with the AdBlue reaching further into the fuel system with each mile. Tell us roughly how far it had come. Wherever your car came to a stop is where all of it gets done, even with more to flush after the engine has been started. Lasting damage is very unusual when it is noticed soon. ## What does an AdBlue drain on a diesel involve around Lanner? A street by War Memorial, a driveway, a layby or a filling station: wherever the car has stopped in Lanner, our technicians travel to it. Which fluid got in, roughly the quantity, and whether your motor has turned over: our technicians ask first, because those decide the work. Then your tank is drained where the car stands, so the contaminated fuel and the AdBlue come out together. Residue from AdBlue will not flush out unaided, and so the whole system gets a careful flush, which counts much more here than with petrol. Next, your filter: flushed, or replaced if it has to be. After that clean diesel, and then a check of your car. The majority of these jobs are a half-hour visit once we get there, provided your motor hasn't run. Explosion-proof pumps mean a live forecourt safe to work on, and they're quiet enough not to disturb the street at night. The final step is to bleed the system on new diesel. Then our engineers start the car and you set off, whether from a parking bay outside Redruth or a drive in Lanner. The check before our engineers leave is that it runs correctly on clean diesel. As the job is done in its entirety where the car is, a workshop never comes into it. Insurers ask for a VAT invoice and an engineer report, and both come at the end. ## About Lanner Lanner is a village in Cornwall, situated inland at an elevation of 112 metres, approximately 7.4 miles from the city of Truro. Lanner is characterised by its predominantly detached housing stock and is surrounded by nearby places such as Pennance, Tresavean, and Treviskey. Lanner has a population of around 1628 residents and is located about 238.5 miles west of London. ## AdBlue drains around Lanner and across Cornwall Pennance, Tresavean and Treviskey are among the towns around Lanner that the same vans serve, along with much of Cornwall beyond, over the TR postcode area. Ring and check instead of guessing when you are by a border, or anywhere awkward to explain. Wherever your vehicle stands — a driveway at home, a residential street, a parking area, a forecourt — our technicians empty it on the spot, and there's no need to bring it to us; that suits Lanner, a rural village, well. ## Lanner: what AdBlue in a diesel tank costs to fix Not one single price would be fair, since each job is different. Three things move the cost: whether your engine has run and for how long, how much AdBlue went in, and where the vehicle is. That last one comes down to whether a van can get to it safely, and an open drive is simpler than a tight space behind Lanner Village Hall. That is why each call from Lanner starts with the same three questions, asked before giving a figure, not after: what got in, how much, and if it has run. The answers turn a range into a straight quote. Before anyone sets off, you hear the quote by phone. And you pay on the day, card or over the phone, with nothing upfront. While our engineer is on the way, dig out your insurance: many include misfuelling. ## Lanner: still next to the vehicle? In that case, touch nothing — that is the best step available. Keys out; engine and ignition off. Call 0333 366 0103 then tell us it is AdBlue, roughly how much, and if it's run. Petrol in Diesel takes it from there, around Lanner or anywhere around Cornwall.