--- title: AdBlue in a Diesel Tank Knettishall: Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/knettishall-suffolk/ location: Knettishall county: Suffolk latitude: 52.386770 longitude: 0.897180 service: AdBlue in a Diesel Tank updated: 2026-10-22 --- # Why It Happens and How to Prevent It: AdBlue in a Diesel Tank in Knettishall Pause here a minute if the diesel tank already holds AdBlue in it: ignition off, engine off, then ring 0333 366 0103. Caught before the engine runs, it's usually a drain and a thorough flush, done where the vehicle is in Knettishall. Reading before the event? Then the rest explains why it happens and what to stop it happening at all. ## AdBlue in a diesel car: two tanks, two fillers Many current diesels on the roads around Knettishall and Market Weston carry two liquids, not one. Diesel goes to your motor. AdBlue goes to your exhaust, where it is sprayed into the gas to fresh it, and it lives in a tank of its own. Each tank has its own filler. Other vehicles keep the AdBlue filler in the boot or under the bonnet; plenty of others have the two together under one flap. At the petrol pump, the diesel side gets filled all the time. The AdBlue side is fuelled far less often, normally from a bottle, and normally by someone who has to stop and think where it goes. Mistakes happen in that gap between the two. ## Knettishall: how AdBlue in the diesel tank takes place It's hardly ever carelessness. Three things tend to line up. Hurry comes from the warning. The car tells you as AdBlue runs low, and an empty tank puts it into limp mode — so the top-up happens quickly, before work on a driveway off Heath Road, or on the way home in the car park at the pub in the village. Then the vehicle is unfamiliar. A hire car, a new vehicle or a company car puts the fillers where your last one did not, and your hand hits for the cap it would have used on the old one. A spout-topped bottle meets no obstacle at a diesel filler no more than at an AdBlue one. And so the pour, once begun, carries on. Gasthorpe or the middle of Knettishall: it is the same few seconds either way. ## Which filler is for AdBlue, and which for diesel? Whether a Knettishall forecourt or a drive out in Garboldisham, take a couple of seconds on these before anything goes in. - Read the cap rather than going by where it sits: AdBlue caps are regularly blue or marked "AdBlue", and diesel caps usually are not. - On plenty of cars, the size tells: AdBlue has the smaller filler neck. - Lift the flap and look for a label — plenty of vehicles mark which goes in which inlet just there. - The handbook shows which it is if the filler is not next to your diesel cap: the boot, or under the bonnet. - Ask the person who drove it last — before you leave, not when the light comes on — when you pick up a hire or company car from somewhere like the car park outside Harling Road. ## Keeping AdBlue out of the diesel tank when you top up Wherever across Suffolk the light comes on, this is a routine for the day. - Not in a rush on the side of The Street, not on a slope, not with your engine running: park and switch off properly. - Daft as it sounds, saying "AdBlue" out loud while you unscrew the cap does the trick — after you've found the filler and read the cap. - Both behind one flap? So make sure the lid on your diesel filler is still shut before lifting the bottle. - Finish when that tank is topped up or the bottle runs dry; until then, pour gently using the built-in spout. - Close the cap and check a second time. Make sure the diesel cap was never opened. Only then start your car. Stop there if you find, at stage two or three, that you have already poured into the diesel side. Never carry on to step five. ## Put AdBlue in the diesel tank around Knettishall already? Short order, then. First: your motor stays off. On many diesels the ignition alone runs the fuel pump, so don't switch the car on. Do not top up with diesel to thin it: AdBlue doesn't mix with diesel, it sinks to the bottom of your tank, where your fuel is sucked from. On a forecourt — Shell, another forecourt nearby or another — the staff will normally help roll your car clear, when you ask. At home in Knettishall? Then your car remains where it is. Stop as soon as it is safe and switch off, if your engine has already run. Leave the M11 — under 50 miles out of Knettishall — at the first junction. A short hop across Knettishall is a smaller job than a run towards Norwich, under 25 miles away, so tell us roughly how far it went. ## Knettishall: what happens when our engineers turn up The van comes to the vehicle anywhere it has come to rest — your own drive, beside Saint Peter's Church, or outside Hopton Church of England Primary Academy. Our engineers ask what went in, about how much, and if it's run, since the replies settle the work and the price. Nobody sets off until you've heard the quote by phone. Your system is then cleaned thoroughly, after the tank is cleared. Unlike petrol, AdBlue leaves crystals and eats at some fuel-system metals, and none of that washes out by itself. That is why it counts more. Filter flushed or, if it must be, replaced; fresh diesel in; then a test of the car. We do not go until it has been started and is running correctly. If your motor hasn't run, most jobs take about half an hour once we are there, using pumps that are fine on a busy forecourt and quiet enough to use outside a house at night. Your insurer usually wants an engineer's report and the VAT invoice, and both are yours at the end. Payment is on the day, with no deposit. Wrong-fuel cover is included in plenty of insurance policies — and so use the wait to check yours. ## About Knettishall itself Knettishall is a small hamlet situated on the riverside in Suffolk, with an elevation of around 20 metres. Knettishall lies near the villages of Gasthorpe, Hopton, and Coney Weston, and is approximately 23.6 miles from Norwich. Knettishall has a population of around 510 people, predominantly living in detached houses. Knettishall is located in the Eastern region of England, about 74.8 miles from London. ## Knettishall and Suffolk: AdBlue drains across the area Being a rural hamlet, Knettishall shares its vans nearby areas — Hopton, Coney Weston — right across IP postcodes and the surrounding area around them. A postcode starting IP22 2 gets our van to you fastest. There's no need to shift the vehicle. Our technicians drain it where it is — a side street near Saint Nicholas, a lay-by on the way to Six Acre Covert, a driveway. Ring and ask rather than assuming if you're near a border, or somewhere hard to explain, like the back of Hut Hill. ## Knettishall people: the short version Always, the cap; after that, the pour. AdBlue in your diesel tank regardless? Leave the car off then ring 0333 366 0103; Petrol in Diesel empties it where it stands, throughout Suffolk.