--- title: Explained: AdBlue in a Diesel Tank Oadby canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/oadby-leicestershire/ location: Oadby county: Leicestershire latitude: 52.596820 longitude: -1.076180 service: AdBlue in a Diesel Tank updated: 2026-10-04 --- # Oadby: How Does AdBlue End Up in a Diesel Tank, and How Do You Prevent It? AdBlue already in your diesel tank? Then put this page down a moment, leave your ignition and motor off, and phone 0333 366 0103. Caught before your motor runs, it's normally a drain and a thorough flush, done where your car is around Oadby. Here in advance? In that case what follows covers how it comes about and how to stop it ever happening. ## AdBlue in a diesel car: two tanks, two fillers Not one fluid but two: that is what many modern diesels near Oadby and Wigston carry, with diesel for the engine. The exhaust, not the motor, is where AdBlue goes: sprayed into the gas to fresh them, from a separate tank. Each tank has its own filler. Some motors keep the AdBlue filler in your boot or under the bonnet; plenty of others have the two side by side under one flap. At the petrol pump, your diesel side is topped up constantly. Much less often, the AdBlue side gets filled — mostly from a bottle, by someone working out where it goes. The mistake lives in that gap. ## AdBlue in the diesel tank in Oadby: how it takes place Carelessness seldom causes it. What does is three things coming up at once. On a drive off Ward's End before work, or in the car park at The Wheel Inn heading home: that's where the hurried top-up happens. Why the rush? As AdBlue gets low the car warns you, and if it's empty, limp mode kicks in. The old car's cap is where your hand goes — but a hire car, a new vehicle or a company car keeps the fillers somewhere else. That is the second thing: a strange motor. 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 after it has started. South Knighton or the middle of Oadby: it takes the same few seconds in both. ## The AdBlue filler and your diesel filler: telling them apart A couple of seconds is all these take — so check them before you tip anything, on a drive in Stoneygate or a forecourt around Oadby. - The cap. The AdBlue cap is commonly blue, or marked "AdBlue". Your diesel cap usually is not. Read it instead of going by where it sits. - Plenty of motors fit AdBlue the smaller filler of the two. - Look inside the fuel flap: plenty of cars carry a label there saying which fuel goes where. - In your boot or under the bonnet: that's where the filler is 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 outside South Wigston, ask before you leave, not when the light comes on. ## Topping up AdBlue without it reaching the diesel tank On the day the warning comes on — wherever it is across Leicestershire — a routine to follow. - Not in a rush on the side of The Morwoods, not on a slope, not with the engine running: park then switch off properly. - Silly as it sounds, speaking "AdBlue" out loud while you unscrew the cap does the trick — after you have located your filler and read it. - Leave your diesel cap on. If both sit under one flap, check your diesel cap is still closed before you lift the bottle. - Using the bottle's own spout, pour slowly — and stop when it is full or the bottle is empty. - Only then, start the car: close the cap, check a second time, and make sure the diesel cap was never opened. Discover at the second or third step that the bottle went into the wrong filler? That is where you stop. Don't carry on to step five. ## Oadby: already put AdBlue in your diesel tank? The short order of things, starting with no starting your motor. Keep the ignition off as well, since on many diesels it alone runs your pump. Don't top up with diesel to dilute it: AdBlue does not mix with diesel, it sinks to the bottom of that tank, where the fuel is drawn from. The attendants at Sainsbury's, Esso or any forecourt will normally lend a hand pushing your car away if you ask. If you are on your own drive around Oadby, leave the vehicle where it sits. Already run? Pull over when it's sensible, then switch off. On the M1, under 5 miles from Oadby, that means the next junction. Tell us roughly how far it went: a run towards Leicester, under 5 miles away, is a bigger job than a short hop across Oadby. ## Our arrival around Oadby, and what takes place next The van reaches the car wherever it has come to rest — your own drive, near St Peters Church Hall, or by Launde Primary School. Both the work and the quote rest on three replies — what liquid, which amount, and if it has run — so we ask. Nobody heads out until you've had our quote over the phone. Your system is then cleaned thoroughly, after that tank is drained. Unlike petrol, AdBlue forms crystals and eats at some fuel-system metals, and none of that washes out by itself. Hence it matters more. A test comes at the end: before that, clean diesel is added, and the filter is flushed or changed as needed. After that we fire it up and check it runs properly before we go. Using pumps fine on a busy forecourt and quiet enough to use outside a house at night, most jobs where the engine hasn't run need about half an hour once our technicians arrive. The insurer will ask for the engineer's report and your VAT invoice, and both are yours once this job is done. Payment comes on the day, with no deposit. It is worth looking at your insurance as the van travels to you: misfuelling cover comes with plenty of policies. ## About Oadby and where it is Oadby is a locality situated on the River Soar in Leicestershire, with a mix of semi-detached housing and other residential properties. Oadby lies close to the city of Leicester, approximately 3.5 miles to the south-east, and is near other local places such as South Knighton and Wigston Magna. Oadby has a population of around 3287 people and is set in a relatively low-lying area at about 97 metres above sea level. Oadby is also within commuting distance of London, being around 85.4 miles north-west of the capital. ## AdBlue drains around Oadby, and Leicestershire beyond Wigston Magna and Stoughton are among the towns around Oadby, a small village, that the same vans cover, throughout LE postcodes. Quote a postcode that starts LE2 5, and our van gets there quickest. Your car stays put. Our technicians drain it where it is — a side street close to Oadby War Memorial, a lay-by on the way to Uplands Park, a driveway. Ring and ask instead of guessing if you're close to a border, or somewhere hard to explain, like the back of St Peter. ## Oadby drivers: the short version Tip no AdBlue until you've read the cap. Petrol in Diesel drains it on the spot, anywhere around Leicestershire, if AdBlue has gone in your diesel tank anyway — and so leave it off and call 0333 366 0103.