--- title: AdBlue in a Diesel Tank Byfleet: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/byfleet-surrey/ location: Byfleet county: Surrey latitude: 51.338400 longitude: -0.473740 service: AdBlue in a Diesel Tank updated: 2026-10-27 --- # Avoiding AdBlue in a Diesel Tank in Byfleet: Why It Happens If AdBlue is already in your diesel tank, stop reading for a moment: leave the motor and the ignition off and phone 0333 366 0103. Around Byfleet, catching it before your motor runs usually leaves draining and a full flush where it stands. Here in advance? In that case the rest covers how it comes about and how to prevent it ever happening. ## AdBlue in a diesel car: two tanks, two fillers Plenty of modern diesels on the roads about Byfleet and St Georges Hill carry two liquids, not one. Diesel goes to the motor. AdBlue goes to your exhaust, where it is sprayed into the gas to clean it, and it lives in a tank of its own. Each tank has its own filler. Many of motors have a single flap for the two, while others move the AdBlue filler to the boot or under the bonnet. At the petrol pump, the diesel side gets filled all the time. Someone who has to stop and work out where it goes usually tops up the AdBlue side, from a bottle, and much less often. The mistake grows in that gap between the two. ## Byfleet: how AdBlue in your diesel tank happens Seldom is it carelessness: normally three things coincide. On a drive off Binfield Road before work, or in the car park at The Plough heading home: that is where the rushed top-up happens. Why the rush? As AdBlue runs low the car warns you, and once it's gone, limp mode follows. Next, the hand goes for the cap it knew on the old vehicle — since a hire car, a new car or a company car puts the fillers somewhere your last one did not. Lastly, the spout fits: diesel filler or AdBlue filler, it goes in just as readily, and after the pour starts, nothing halts it. Brooklands or the heart of Byfleet: it is the same few seconds either way. ## The AdBlue filler and your diesel filler: telling them apart Whether a Byfleet forecourt or a drive out in New Haw, spend a few seconds on these before any is poured in. - Check the cap rather than going by where it sits: AdBlue ones are often blue or marked "AdBlue", and diesel caps usually aren't. - Many cars give AdBlue the smaller filler of the two. - Open the filler flap and check for a label — many motors mark what goes in each filler right there. - In your boot or under the bonnet: that is where the filler sits if it is not by the diesel cap, and the handbook tells you which. - The person who drove the vehicle last. On a hire or company car collected from somewhere like the car park at Byfleet & New Haw, ask before you leave, not when the light comes on. ## Keeping AdBlue out of the diesel tank when you top up A routine for the day the light comes on, wherever around Surrey that is. - Pull in somewhere level, engine off, with time to spare — never rushing on the side of Brewery Lane. - Daft as it sounds, saying "AdBlue" out loud as you unscrew the cap works — after you have found the filler and read the cap. - The diesel cap stays on. Where both sit under a flap, confirm it is closed before the bottle comes up. - Using the bottle's own spout, tip slowly — and stop when it is full or the bottle is empty. - Close the cap, and check again — making sure your diesel filler remained shut throughout. Only then, start the car. Stop there if you find, at step two or three, that you've already poured into your diesel side. Do not go on to step five. ## Already put AdBlue in the diesel tank around Byfleet? Brief order, then. First: the engine remains off. On many diesels the ignition alone runs the fuel pump, so don't switch the vehicle on. AdBlue does not mix with diesel — it sinks to the bottom of your tank, where your fuel is drawn from — so don't top up with diesel to thin it. The attendants at Tesco, JET or any forecourt will normally lend a hand pushing your car away when asked. Leave it where it is if you are on your own drive around Byfleet. Already run? Pull over when it is sensible, then turn off. On the M25, under a mile from Byfleet, that means the next junction. A short hop across Byfleet is a smaller job than a run towards Westminster, under 25 miles away, and so tell us about how far it went. ## Byfleet: what occurs when our engineers arrive Our van comes to the car wherever it has come to rest — your own drive, beside Byfleet Community Library, or by St Mary's CofE Controlled Primary School, Byfleet. Those answers decide the work and the price, so our engineers ask what got in, roughly how much, and whether it has run. That quote comes on the call, ahead of any van leaving. Draining that tank comes next, followed by a full flush of the system. With AdBlue that counts more than with petrol: it crystallises and is corrosive to some of the metals in a fuel system, so it doesn't wash out on its own. The filter cleaned or, where it must be, replaced; fresh diesel in; then a test of your vehicle. Before leaving, our engineers fire it up and confirm that it is running properly. If your motor has not run, most jobs take about half an hour once we are there, using pumps that are safe on a working forecourt and quiet enough to use outside a house after dark. Paying is on the day, not upfront, and you are given the documents your insurer wants: an engineer's report and a VAT invoice. It is worth checking your insurance as the van travels to you: misfuelling cover is included with many policies. ## About Byfleet Byfleet is a village in Surrey, situated on the River Wey and adjacent to the River Thames, with a low elevation of around 18 metres. Byfleet has a mix of housing types, but semi-detached homes are predominant, and is located near other notable places such as Brooklands and Wisley. Byfleet is also close to West Byfleet, with which it shares some amenities. Byfleet has a population of approximately 4031 residents and is within commuting distance of London, being around 18.9 miles from the city centre. ## AdBlue drains around Byfleet and across Surrey Byfleet is a village, and the vans that cover it also work the places near it, Wisley and West Byfleet among them, across the KT postcode area. A postcode starting KT14 7 gets our van to you fastest. Shifting the vehicle isn't necessary. The drain happens right there, be it a driveway, a street near Byfleet Village Hall, or a layby towards Byfleet Village Green. Ring and ask rather than assuming if you're close to a border, or somewhere hard to describe, like the back of Byfleet Methodist Church. ## Byfleet people: the short version Tip nothing until you have read the cap. Still AdBlue in the diesel tank? Petrol in Diesel can empty it where it stands, wherever in Surrey: switch the vehicle off then phone 0333 366 0103.