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Petrol in Diesel

0333 366 0103

Sowhill: How Does AdBlue End Up in a Diesel Tank, and How Do You Avoid It?

Stop reading for a moment if your diesel tank already holds AdBlue in it: ignition off, engine off, then phone 0333 366 0103. A drain plus a full flush, carried out just where your car sits around Sowhill, is normally what it needs when found before the motor runs. The rest of this page covers why it happens and how to ensure it does not — useful if you are reading ahead of time.

Call 0333 366 0103

AdBlue in a diesel car, and its separate tank

No single liquid but two: that's what many modern diesels around Sowhill and Cwm Fields run, with diesel feeding the motor. The exhaust, not the engine, is where AdBlue ends up: dosed into the fumes to fresh it, from a separate tank.

Every tank has a filler of its own. Some motors put the AdBlue filler in your boot or under the bonnet; plenty of others place both together behind one flap. Filling your diesel side at the pump goes on all the time. Rarely topped up, AdBlue normally comes from a bottle, poured by a driver who has to stop and think what cap to use. It's in that gap that the error happens.

AdBlue in the diesel tank in Sowhill: how it happens

Three things tend to line up, and carelessness is rarely one of them.

Hurry follows from the warning. The car warns you as AdBlue runs low, and a dry tank puts the vehicle into limp mode — so the top-up happens in a rush, before work on a drive off Bryngwyn Road, or on the way home in the car park outside The Dragonffli.

Unfamiliar motors come next, too. Rentals, new vehicles and company vehicles place their fillers in new places, and habit goes for the cap 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, and so nothing stops the tip after it has started. Lower Race or the heart of Sowhill: it takes the same few seconds in both.

Flushing a diesel fuel system after AdBlue, Sowhill

Which filler is for AdBlue, and which for diesel?

Check these before pouring, on a forecourt around Sowhill or a drive over in Upper Race. Seconds, no more.

  • Read the cap instead of going by position: AdBlue caps are frequently blue or marked "AdBlue", and diesel ones usually aren't.
  • Many cars fit AdBlue the smaller filler of the two.
  • Open the filler flap and look for a label — plenty of vehicles mark what belongs in which filler just there.
  • The handbook says where it is if your filler is not next to the diesel cap: the boot, or under the bonnet.
  • Collecting a hire or company car, say at the car park at Pontypool and New Inn? Ask the person who drove the vehicle last before leaving, not when 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 Torfaen that is.

  • Park then switch off. Not on a slope, not with the engine running, and not in a rush on the side of Twmpath Gardens.
  • Say "AdBlue" out loud as you unscrew the cap, once finding the AdBlue filler and reading it. Silly, yes, but it works.
  • The diesel cap stays on. When both sit under a flap, confirm it is shut before lifting the bottle.
  • Using the bottle's own spout, pour slowly — and stop when it is full or the bottle is empty.
  • Close the cap, then look again — making sure your diesel cap remained closed the whole time. Only then, start the car.

Spot at step two or three that it has already gone into your diesel side? Then stop right there. Skip step five altogether.

AdBlue in your diesel tank already, in Sowhill?

Short list, then. First: your engine remains unstarted. Do not switch the ignition on; on plenty of diesels that alone runs the fuel pump. Topping up with diesel won't dilute it: rather than mixing, AdBlue sinks to the base of the tank, just where fuel is drawn from.

If you are at a forecourt, whether it's the the nearest petrol station or the Tesco, ask the staff to help push the vehicle away from the pump. If you're on your own driveway in Sowhill, leave the vehicle where it sits.

If the motor has already run, stop as soon as it is safe then switch off. On the M4, under 10 miles from Sowhill, that means the next exit. A short hop across Sowhill is a smaller job than a run towards Newport, under 10 miles away, so tell us roughly how far it went.

Sowhill: what occurs when our engineers get there

Outside the local primary school, close to Civic Centre or on your own drive: wherever your car has stopped, we come to it. Both the work and the quote depend on three replies — which fluid, what amount, and if it's run — so our engineers ask. Nobody heads out before you've had our quote by phone.

Then the tank is drained and your system rinsed thoroughly. 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. The fuel filter is cleaned, or replaced where it needs to be; fresh diesel goes in; and the vehicle is tested. Then we start the engine and check it runs properly before leaving.

Unstarted vehicles usually need a half-hour visit from arrival. The kit is fine on a live forecourt, and hushed enough for a driveway late at night. Your insurer will ask for an engineer's report and your VAT invoice, and both are yours at the end. Payment comes on the day, with no money upfront. Wrong-fuel cover is included in many insurance policies — and so use the wait to look at yours.

About Sowhill and where it is

Sowhill is a suburban area in Torfaen, situated on the riverside with an elevation of around 160 metres. Sowhill lies near the city of Newport, approximately 7.9 miles away, and is close to nearby places such as Lower Race, Pontypool, and Tranch. Sowhill has a population of around 2404 people and predominantly consists of semi-detached housing.

AdBlue drains around Sowhill and across Torfaen

Pontypool and Tranch are among the places around Sowhill, a residential suburb, that the same teams cover, throughout NP postcodes. Fastest of all: give a NP4 6 postcode for the van.

The car does not need to move. Our technicians drain it where it is — a side street close to Pontypool Indoor Market, a lay-by on the way to Church Wood, a drive. Assuming doesn't help at the back of Platfform Torfaen Hub, close to a boundary, or anywhere hard to describe; phone and ask.

Sowhill people: the short version

Tip nothing till you have read the cap. Even so AdBlue in your diesel tank? Petrol in Diesel can drain it wherever it is, wherever around Torfaen: keep it off then call 0333 366 0103.

Call 0333 366 0103