--- title: Keymer: AdBlue in a Diesel Tank, Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/keymer-west-sussex/ location: Keymer county: West Sussex latitude: 50.922440 longitude: -0.132510 service: AdBlue in a Diesel Tank updated: 2026-10-06 --- # Avoiding AdBlue in a Diesel Tank in Keymer: Why It Occurs Leave the motor and ignition off and phone 0333 366 0103 first — reading can wait if AdBlue is already in your diesel tank. A drain and a thorough flush, carried out right where your car stands in Keymer, is usually all it takes when caught before your motor runs. Reading before the event? In that case what follows explains how it happens and how to stop it happening at all. ## Why does AdBlue in a diesel vehicle need its own filler? Not one liquid but two: that is how plenty of newer diesels around Keymer and Hurst Wickham carry, with diesel feeding the engine. AdBlue's own tank keeps it, and from there it is sent to the exhaust, where spraying treats the fumes. Different tanks, different fillers. Under one flap, side by side: that's the arrangement on many vehicles. On others, AdBlue's filler sits under the bonnet or in your boot instead. Topping up your diesel side at the petrol pump goes on all the time. Rarely topped up, AdBlue usually comes from a bottle, poured by someone who must stop and think what filler it needs. That gap is where the mistake lives. ## How AdBlue in your diesel tank occurs in Keymer Carelessness seldom causes it. Instead is three things coming up at once. On a drive off Keymer Road before work, or in the car park outside The Greyhound on the way home: that's where the hurried top-up takes place. Why the rush? As AdBlue gets low the car warns you, and if it's gone, limp mode kicks in. Then, your hand goes for the cap it knew on the old vehicle — because a hire car, a new car or a company car puts the fillers where your last one didn't. A spouted bottle finds no resistance at a diesel filler any more than at an AdBlue one. So the tip, after started, keeps on. Hassocks or the middle of Keymer: it takes the same few seconds either way. ## Which filler is for AdBlue, and which for diesel? A couple of seconds is all the checks take — so check them before you tip anything, on a driveway in Westmeston or a forecourt in Keymer. - Colour and lettering: an AdBlue cap is often blue, or says "AdBlue", where a diesel cap usually does not. Trust the cap, not where it sits. - Check the size: the smaller neck is, on many cars, the AdBlue one. - The flap. Look inside the fuel flap for a label. Many motors say there which fuel goes where. - The handbook. If your filler is not by your diesel cap, it's in the boot or under the bonnet, and the handbook says which. - Ask the person who drove it last — before you leave, not when the light comes on — if you pick up a hire or company car from somewhere like the car park at Hassocks. ## AdBlue top-ups that never reach your diesel tank A routine for the day the light comes on, wherever around West Sussex that is. - Not in a rush on the side of Church Mead, not on a slope, not with the motor running: park then switch off first. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds silly and it works. - Leave the diesel cap on. If both sit under one flap, check the diesel cap is still closed before you lift the bottle. - Gently does it, through the bottle's own spout, until it's full or the bottle is empty. - Before you start the vehicle, close the cap and check again that the diesel cap never opened off. Find during the second or third step that the bottle went in the wrong filler? That's where you stop. Don't carry on to step five. ## Put AdBlue in your diesel tank in Keymer already? Do not start your motor: that's where the short order of things begins. On plenty of diesels the ignition alone runs the fuel pump, and so don't switch it on. Thinning it with extra diesel won't work, since AdBlue sinks to the base rather than blending — and that is where your fuel is drawn from. Ask the attendants to help push the vehicle away from the pump if you are at a forecourt — the Esso, the Tesco or anywhere else. If you're on your own drive in Keymer, leave the vehicle where it is. If the engine has already run, stop as soon as it is safe then switch off. The next exit means where to leave when you are on the M23, under 15 miles from Keymer. Mileage matters — a short hop across Keymer makes a smaller job than driving under 10 miles towards Brighton and Hove — so tell us about how far it went. ## When we arrive in Keymer, what occurs? By The Windmills Junior School, near St Edward The Confessor or on your own drive: wherever your car has stopped, our engineers come to it. The answers determine the work and our price, so our engineers ask what was put in, about how much, and whether it's run. You get that price by phone, before anybody sets off. Then the tank is cleared and your system rinsed thoroughly. Not like petrol, AdBlue forms crystals and eats at certain fuel-system metals, and none of that clears out unaided. That is why it matters more. Your filter is cleaned, or replaced where it needs to be; clean diesel goes in; and your car is tested. We do not leave until it has been fired up and is running properly. If the engine has not run, most jobs take about half an hour once we are there, using pumps that are safe on a busy forecourt and quiet enough to use outside a house after dark. Nothing in advance; you settle up on the day. Afterwards, the VAT invoice and a report from the engineer go to you for the insurer. It's worth looking at your insurance as the van travels to you: misfuelling cover comes with many policies. ## About Keymer and where it is Keymer is a village in West Sussex, situated inland at an elevation of 56 metres, approximately 6.8 miles north of Brighton and Hove. Keymer lies near the villages of Hassocks, Ditchling, and Clayton, and is characterized by its predominantly detached housing stock. Keymer has a population of around 2136 residents, and is located about 40.4 miles south of London. ## AdBlue drains round Keymer, and West Sussex beyond As a rural village, Keymer shares its vans nearby areas — Ditchling, Clayton — right through BN postcodes and the wider area around them. Fastest of all: quote a BN6 8 postcode to the van. There's no need to shift the vehicle. Draining happens on the spot, whether a driveway, a road near Hassocks Library, or a lay-by towards Keymer Cricket Club. Guessing doesn't help at the back of St Cosmas & St Damian, on a border, or somewhere hard to pin down; ring and check. ## Keymer drivers: the short version First, the cap; after that, the tip. AdBlue in the diesel tank after all? Leave it switched off then ring 0333 366 0103; Petrol in Diesel drains it where it stands, throughout West Sussex.