Can a blocked DPF cause an AdBlue warning
Can a blocked DPF cause an AdBlue warning — they are separate faults, but a vehicle with sustained exhaust problems can log codes in both systems. The codes, not the lamp, tell you which.
Call 01293 248666 Call-out from £89
Can a blocked DPF cause an AdBlue warning — the context
SCR and a DPF are two separate systems on the same exhaust. The DPF traps soot particles and burns them off. SCR uses AdBlue to convert NOx into nitrogen and water. A DPF problem is not an AdBlue problem.
What a DPF does. The diesel particulate filter is a mechanical trap. Soot collects in it and is periodically burnt off in a regeneration cycle, which needs heat and therefore needs a decent run. A blocked DPF is a soot problem, and it is solved with heat, not with fluid.
What SCR does. Selective catalytic reduction is chemistry, not filtration. A metering pump and a dosing injector spray AdBlue into the hot exhaust stream ahead of the catalyst. The urea decomposes to ammonia, and the ammonia reacts with nitrogen oxides across the catalyst to produce nitrogen and water.
The cheapest possible version of almost every AdBlue problem is the one where the engine was never started after the mistake. That single decision moves more money than anything else discussed on this site.
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
Every brand above belongs to Fuel Fixer International, owned by Stockbridge Capital Holdings. The directory lives on the operator's own site: forecourtassist.co.uk/network.