01293 248666
4.8/5 from 2,190 Trustpilot reviews 24 hours, UK-wideCall-out from £89 — quoted before anyone travelsFuel Fixer Ltd · company 08520551

I started the engine before i realised. what now

Short answer

I started the engine before i realised. what now — say so on the phone. If it ran only briefly the job is usually still a drain, a flush and a filter, with a fuel-system pressure check. If it ran long enough to run rough or cut out, injectors and the high-pressure pump may need testing, and that is quoted separately.

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Answered by Rambo S, Wrong Fuel Expert at Fuel Fixer International.

I started the engine before i realised. what now — the context

AdBlue is AUS 32 — 32.5% urea in demineralised water — with a density around 1.09 g/cm³ against diesel's roughly 0.83. It does not dissolve into diesel. It sinks, and it settles exactly where the fuel pickup sits. The moment the engine turns over, the lift pump draws urea solution through the filter and into the high-pressure pump and injectors, which are lubricated by diesel and are not designed to see water or urea. Urea also crystallises as it dries and attacks copper, brass, aluminium, zinc and mild steel.

If you have put AdBlue in diesel, do not start the engine — call 01293 248666. AdBlue is water-based and sinks to the bottom of the tank, so a drain and flush before the engine runs almost always fixes it.

The problem behind this question
TopicAdBlue in diesel
SeverityRecoverable Normally put right by a drain and flush, provided the engine has not been run.
Typical costCall-out £89 to £199 · drain £199 to £1,999
Time on siteAbout 60 minutes
Helpline01293 248666

Most bad advice on this subject comes from treating the SCR system as if it were part of the engine. It is not. It sits in the exhaust, downstream of combustion, and nothing poured into the AdBlue tank ever reaches a piston.

The call-out is £89 to £199. An AdBlue tank drain and flush is quoted on the phone before a technician travels. If the SCR system needs component replacement — dosing injector, pump, tank or catalyst — that is separate, and you will be told before any work starts. If this is a job we cannot fix at the roadside, we will tell you that on the phone rather than after we arrive.

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What customers say

4.8 out of 5 from 2,190 Trustpilot reviews. What reviewers mention most is that the technician stayed calm and professional with a driver who was embarrassed and stressed, and that somebody arrived when they said they would.

The most common criticism is price. People do not expect a wrong-fluid job to cost what it costs, and that is a fair complaint to publish rather than bury. The answer is the Call-out from £89, a quote given on the phone before a technician travels, and being told when a job cannot be done at the roadside rather than after somebody has arrived and charged for the visit.

Who you are dealing with

Work booked through AdBlue in Fuel is carried out by Fuel Fixer Ltd, company no 08520551, registered at Fairway House, Portland Road, East Grinstead, RH19 4ET, trading as Forecourt Assistance and part of Fuel Fixer International, which is owned by Stockbridge Capital Holdings.

Reference: Selective catalytic reduction (Wikipedia).

Across the Fuel Fixer network

AdBlue in Fuel is a service by Forecourt Assistance, a brand of Fuel Fixer International, owned by Stockbridge Capital Holdings. The full group directory is at forecourtassist.co.uk/network.