How to fix a P20E8 fault code
P20E8 can be a worn AdBlue pump, a blocked line or fluid that has frozen, and each one costs a different amount to put right. A £100 + VAT diagnostic where the vehicle is parked shows which you're facing.
Fix options for P20E8 compared
| Fix | When it's the answer | Where it's done | Price |
|---|---|---|---|
| Mobile diagnostics | First, to read dosing pressure and find where it's being lost | Your home or workplace | £100 + VAT |
| New AdBlue pump or pump filter | Pressure won't build with a healthy supply | Dealer or SCR specialist garage | Garage quote |
| Clearing or replacing a crystallised line | Pressure builds then drops, white deposits on the pipework | Dealer or SCR specialist garage | Garage quote |
| AdBlue delete (software) | When you'd rather not repair the system | Your home or workplace | £330 + VAT |
What P20E8 means
The official wording is Reductant pressure too low. Reductant is the generic name for AdBlue, and the ECU has found the pump isn't building enough pressure in the line to the dosing injector.
What causes P20E8
- A worn or failing AdBlue pump
- A blocked filter in the pump unit
- AdBlue crystallised in the line or around the injector
- Fluid that has frozen in very cold weather (AdBlue freezes at around minus 11°C), especially if a tank heater has failed
- A split or leaking supply line
- A wiring or connector fault at the pump
Symptoms you may notice
The AdBlue warning and engine management light usually come on together, and many vehicles then show a no-restart countdown. Performance often feels unchanged, so the countdown message is what gets noticed.
If the code only appears on frosty mornings, freezing or a heater fault is a strong lead. A crusty white build-up under the vehicle points towards a leak or crystallisation instead.
Using the vehicle with P20E8
You can usually keep going for now, but on Euro 6 vehicles the countdown keeps running while the fault is there. Once it reaches zero the engine won't restart after switching off, so get it diagnosed while you still have room on the counter.
What happens on a P20E8 visit
Confirm the booking
Diagnostics is £100 + VAT at your home or workplace.
Read the AdBlue system
We check the codes, dosing pressure, pump activity and countdown status, and look along the lines for leaks or crystals.
Get the answer
You'll know whether it's the pump, a line, freezing or wiring. We don't repair AdBlue systems, so repairs go to a dealer or SCR specialist with our findings.
The delete option
An AdBlue delete is £330 + VAT and carried out on site.
How much does it cost to fix P20E8?
That depends on what has failed. A crystallised line is usually cheaper than a pump, and the dealer or SCR garage quotes once the diagnostic has shown which part it is.
Is it worth fixing P20E8 on an older or high-mileage vehicle?
Usually, yes, as the countdown will eventually stop it restarting. Weigh the repair quote against the vehicle's value once you know the cause.
Will replacing the AdBlue pump always clear P20E8?
Not if a line is blocked or the tank heater has failed. A new pump pushing into a crystallised line still can't hold pressure, so test before buying.
Can you sort P20E8 at my home or workplace?
We diagnose it there. Pump and line repairs are dealer or specialist work, and the AdBlue delete is done on site.
Is there a Citroen recall for P20E8?
We can't confirm recalls. If you've got a Citroen such as a C4 Cactus, or a Peugeot Boxer, a dealer can check by registration whether any campaign covers your AdBlue system.
Is an AdBlue delete an option for a road vehicle with P20E8?
No. We carry out AdBlue deletes for off-road and export use only, so a vehicle on UK roads needs the repair. Read Is AdBlue delete legal? for the detail.
Book the right fix for P20E8
Send us the registration and any countdown figure, and we'll confirm the price and a time before anything is booked. Related codes include P20EE and P2047.
More fault codes explained
Eccles, Manchester M30 0SF