--- title: Holbrooks: AdBlue in a Diesel Tank, Explained canonical: https://www.petrolinadieselcar.co.uk/adblue-in-diesel/holbrooks-west-midlands/ location: Holbrooks county: West Midlands latitude: 52.443590 longitude: -1.509460 service: AdBlue in a Diesel Tank updated: 2026-10-15 --- # Why It Occurs and How to Prevent It: AdBlue in a Diesel Tank in Holbrooks If AdBlue is already in your diesel tank, stop reading for a moment: leave the motor and the ignition off and ring 0333 366 0103. Normally, if the motor hasn't turned, it is drained and fully flushed where the car is around Holbrooks. The rest of this page explains why it happens and how to make sure it does not — handy if you are reading before it has happened. ## AdBlue in a diesel motor: two tanks, two fillers No single liquid but two: that's what many modern diesels near Holbrooks and Whitmore Park carry, with diesel feeding your engine. AdBlue's own tank holds it, and from there it is sent to your exhaust, where a spray treats the gas. There is a filler for every tank. Under one flap, side by side: that is the layout on a lot of vehicles. Elsewhere, AdBlue's filler is under the bonnet or in your boot instead. At the pump, your diesel side gets filled all the time. A driver who has to stop and work out where it goes usually fills the AdBlue side, from a bottle, and much less frequently. It's in the gap that the mistake happens. ## Holbrooks: how AdBlue in your diesel tank occurs Rarely is it carelessness: usually three things coincide. On a drive off Holborn Avenue before work, or in the car park outside The Holly Bush on the way home: that is where the rushed top-up happens. Why the rush? As AdBlue gets low the car warns you, and once it's empty, limp mode kicks in. Next, your hand goes for the cap it would have used on the old car — because a hire car, a new car or a company car places the fillers where your last one did not. Lastly, the bottle goes in: a diesel filler or AdBlue filler, it slides in as readily, and after the tip begins, no part halts it. The same few seconds settle it, in the middle of Holbrooks or out in Monks Park. ## The AdBlue filler and the diesel filler: telling them apart Check these first, on a forecourt around Holbrooks or a driveway over in Neals Green. A few seconds, no more. - Position can mislead; the cap does not. AdBlue caps are often blue or bear the name "AdBlue" — diesel ones usually don't. - On plenty of vehicles, size tells: AdBlue gets the smaller filler neck. - A label inside your fuel flap frequently shows which fuel goes where, on many cars. Check for it. - The handbook. If the filler isn't by the diesel cap, it's in your boot or under the bonnet, and the handbook says which. - Collecting a hire or company car, say at the car park outside Coventry Arena? Ask whoever drove it last before leaving, not once the light comes on. ## Keeping AdBlue out of your diesel tank when you top up A routine for the day the light comes on, wherever in West Midlands that is. - Turn off once parked — level ground, motor stopped, and not rushed beside Wood Hill Rise on the verge. - Find the AdBlue filler and read the cap. Say "AdBlue" out loud as you unscrew it. It sounds silly and it does the trick. - The diesel cap remains on. When both share a flap, confirm it is closed before the bottle comes up. - Slowly does it, through the bottle's own spout, till it's full or the bottle is empty. - Only then, start the vehicle: close the cap, check again, and make sure your diesel cap was never opened. If at step two or three you find you have already poured into your diesel side, stop there. Skip stage five entirely. ## Put AdBlue in your diesel tank around Holbrooks already? Do not start the motor: that is how the short order of things begins. Keep the ignition off as well, because on plenty of diesels it by itself starts the fuel pump. AdBlue does not mix with diesel — it sinks to the bottom of the tank, where the fuel is sucked from — so don't top up with diesel to dilute it. Ask the staff to help roll your car clear of the pump if you are at a forecourt — the Shell, the Tesco or anywhere else. On your own drive around Holbrooks? Then your car stays where it is. When the engine has been run by now, pull over safely then turn it off. On the M6, under 3 miles from Holbrooks, that means the next junction. Tell us roughly how far it went: a run towards Coventry, under 3 miles away, is a bigger job than a short hop across Holbrooks. ## Our arrival around Holbrooks, and what takes place next Wherever the vehicle came to rest, be it by Parkgate Primary School, beside St Luke's Church or at home, our van comes to it. Both the work and the quote depend on three answers — which liquid, what amount, and whether it's run — so our technicians ask. The price is given on the call, before any van leaves. Draining your tank comes next, then a thorough flush of your system. With AdBlue that matters more than with petrol: it crystallises and is corrosive to some of the metals in a fuel system, and so it doesn't wash out on its own. A test is at the end: before that, clean diesel is added, and your filter is cleaned or changed as needed. We do not leave until it has been fired up and is running properly. Unstarted vehicles usually need a half-hour visit after the moment we arrive. The kit is fine on a live filling station, and quiet enough for a driveway late at night. You pay on the day, with nothing upfront, and get a VAT invoice and an engineer report for your insurer. Wrong-fuel cover is part of many insurance policies — so make use of the wait to look at yours. ## About Holbrooks Holbrooks is a suburban area located near Coventry in the West Midlands, sitting at an elevation of around 103 metres. Holbrooks is characterized by its predominantly terraced housing stock and is situated close to nearby places such as Monks Park and Rowleys Green. Holbrooks is home to a population of approximately 9533 residents and is within a short distance of Coventry city centre, around 2.5 miles away. Holbrooks is also part of the larger West Midlands region, about 87.4 miles northwest of London. ## Holbrooks and West Midlands: AdBlue drains across the area Being a residential suburb, Holbrooks has the same vans as nearby places — Rowleys Green, Foleshill — all the way across CV postcodes and the wider area around them. A postcode starting CV6 4 gets the van to you fastest. Moving the car is not needed. A driveway, a lay-by on the way to Holbrooks Park, a side street close to Holbrooks Evangelical Church: our engineers drain it where it is. Ring and ask rather than guessing if you are near a border, or somewhere hard to describe, like the back of Holy Family Church. ## The short version for Holbrooks motorists Pour nothing until you've read the cap. AdBlue in the diesel tank regardless? Keep the vehicle switched off and ring 0333 366 0103; Petrol in Diesel empties it on the spot, throughout West Midlands.