How It Happens and How to Prevent It: AdBlue in a Diesel Tank in Cubert
AdBlue already in your diesel tank? In that case set this page down for now, leave the ignition and motor off, and phone 0333 366 0103. Caught before your engine runs, it is usually a drain and a thorough flush, done where the car is in Cubert. Nothing happened yet? Further down, the page explains the why it takes place and the how to prevent it for good.
AdBlue in a diesel car: two tanks, two fillers
Not one fluid but two: that's how many newer diesels around Cubert and Treworgans run, with diesel feeding the 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.
Different tanks, separate fillers. Other vehicles put the AdBlue filler in your boot or under the bonnet; plenty of others place the two side by side behind one flap. Topping up your diesel side at the pump goes on constantly. A driver who has to stop and think where it goes normally fills the AdBlue side, from a bottle, and much less often. That gap is where the slip lives.
Cubert: how AdBlue in your diesel tank happens
Three things tend to come together, and carelessness is seldom one of them.
To start with, the warning. Low AdBlue triggers a warning from the vehicle, and running dry means limp mode — hence a hurried top-up, perhaps before work off Ellenglaze Lane, or outside Smugglers Den Inn on the way home that evening.
Unfamiliar motors come second, as well. Hire cars, new cars and company cars place their fillers in new places, and habit reaches for the cap it used on the old one.
And the bottle fits. A bottle with a spout goes into a diesel filler as easily as an AdBlue one, so nothing stops the tip after it has started. Trevail or the middle of Cubert: it takes the same few seconds in both.
The AdBlue filler and the diesel filler: telling them apart
Be it a Cubert forecourt or a driveway out in Mount, take a couple of seconds on these before anything is poured in.
- Colour and lettering: an AdBlue cap is commonly blue, or says "AdBlue", where a diesel cap usually doesn't. Trust the cap, not its position.
- Plenty of motors fit AdBlue the smaller filler of the two.
- Check inside your fuel flap: many cars have a label there saying which fuel goes where.
- Cannot see it beside your diesel filler? In that case check beneath the bonnet or in the boot — the owner's manual says where.
- The person who drove the vehicle last. On a hire or company car picked up from somewhere like the car park at Newquay, ask before you leave, not when the light comes on.
AdBlue top-ups that never reach the diesel tank
A routine for the day the light comes on, wherever across Cornwall that is.
- Not in a rush on the side of Holywell Road, not on a slope, not with the engine running: park then switch off properly.
- Daft as it sounds, saying "AdBlue" aloud while you unscrew the cap works — after you've found the filler and read the cap.
- If both sit under one flap, check the diesel cap is still closed before you lift the bottle — and leave the car on.
- Gently does it, through the bottle's own spout, until it is full or the bottle runs out.
- Only then, start your car: close the cap, check a second time, and make sure your diesel cap was never opened.
Stop there if you find, at stage two or three, that you've already poured into your diesel side. Don't go on to stage five.
Put AdBlue in the diesel tank around Cubert already?
Short list, then. Top of that: your motor stays off. Leave your ignition off too, since on many diesels switching it on by itself runs the pump. AdBlue does not mix with diesel — it sinks to the bottom of the tank, where the fuel is sucked from — so do not top up with diesel to thin it.
Ask the staff to help push the vehicle clear of the petrol pump if you are on a forecourt — the Esso, the Texaco or anywhere else. If you are on your own driveway in Cubert, leave it where it stands.
Stop as soon as it is safe and switch off, if the engine has already run. Leave the M5 — over 50 miles out of Cubert — at the next junction. Mileage counts — a quick hop across Cubert makes a smaller job than driving under 10 miles towards Truro — so tell us about how far it went.
Cubert: what takes place when our technicians get there
Outside Cubert Primary School, near Cubert Methodist Church or on your own drive: wherever your car has stopped, our engineers come to it. Both the work and our quote rest on three replies — what liquid, what quantity, and if it's run — so our technicians ask. You hear that quote by phone, before anyone heads out.
Draining the tank comes next, followed by a thorough flush of your system. AdBlue crystallises and is corrosive to some of the metals in a fuel system, so it doesn't wash out on its own — which is why that counts more with AdBlue than with petrol. Testing is last: before that, fresh diesel is added, and the filter is flushed or replaced as needed. We don't go until it has been started and is running smoothly.
With pumps safe on a working forecourt and quiet enough to use outside a house at night, most jobs where the engine has not run need about half an hour once our technicians are there. Paying happens on the day, not upfront, and you are given the documents your insurer asks for: an engineer's report and a VAT invoice. Many insurance policies include misfuelling cover, so it is worth checking yours while we are on the way.
About Cubert itself
Cubert is a small village in Cornwall, situated on the north coast near the towns of Truro and Newquay. Cubert sits at an elevation of 87 metres, overlooking the surrounding countryside and the Atlantic Ocean. Cubert is characterised by its predominantly detached housing stock and is close to nearby places such as Trevail, Tresean, and Ellenglaze.
AdBlue drains in Cubert and across Cornwall
Tresean and Ellenglaze are among the towns near Cubert, a coastal village, that the same teams cover, over TR postcodes. A postcode starting TR8 5 gets our van to you fastest.
The vehicle remains put. We drain it where it is — a side street near St. Cubert's, a lay-by on the way to Wild Tribe Wood, a driveway. Awkward to explain, like the back of St Piran's Church? Close to a county line? Asking beats assuming, so phone.
In short, for Cubert motorists
Read the cap before you tip. AdBlue in the diesel tank regardless? Keep it off then call 0333 366 0103; Petrol in Diesel drains it on the spot, across Cornwall.