The reason for running the car at high speed to clear the particle filter. This is potentially caused by issues with the EOLYS system causing the filter to block. This filter is located just in front of the engine by the turbo. Adblue is required to reduce nitrogen oxide emissions in the catalyst located under the car. Audi Q3 2 litre TDi AdBlue® Tank Size 12 litres According to Audi one tank of AdBlue® should last you 8000 miles. (however there are reports from drivers that some vehicles have needed AdBlue® refilling after as little as 3000 or 4000 miles). Audi Q5 2 litre TDi AdBlue® Tank size 23 litres According to Audi one full tank of AdBlue® liquid The Citroen handbook says that in no circumstances should you use truck Adblue. I don't know why though, just reporting what it says. The range of an Adblue tank is supposed to be ~12,000 miles depending on how you drive, and the service interval is 16,000 miles for 1.6 HDI and 20,000 miles for 2.0, both with a 1 year interval. On average the tanks last 150k.before pump burns out or throws low pressure faults. There was a software patch that was installed to help tank last longer but it was no good and is no longer used on the adblue pump ecu. So it's either a new tank or an adblue delete. Cat® C4.4 ACERT Industrial Diesel Engines offer the perfect balance of durability, fuel efficiency and low emissions. Extensively tested on the job, these engines use a range of common rail fuel systems and advanced control systems to deliver maximum uptime in the harshest environment. They have proven they can handle the jeffj. I have a Citroen Cactus C4 BlueHdi 1.6L diesel car 65 reg. It has done ~40k miles and suddenly on a drive home on the motorway 3 days ago, the UREA + SERVICE + ENGINE MANAGEMENT lights came on together with an audible beep with on-screen message saying "Engine fault: Get engine repaired". Eventually, the pump would fail, resulting in the errors you saw on the dashboard. PSA fixed the issue by using an AdBlue cap fitted with a small pressure release valve. If caught in time, a new cap would fix the issue. If not, a new tank was required. Unfortunately for you, your C4 missed the recall and is now outside of the warranty period. Woody said: Like so many others I too have had past adblue issues, and now it seems they're coming back to haunt me again. Three years ago I got the dreaded 700 miles countdown which resulted in a £600-ish bill following Citroen dealer diagnostics and a nox sensor replacement. Last week, whilst driving to work, I had the emissions fault screen I recently bought second hand a Citroen Jumper 2.0 96KW mod.2016 with 258000klm. After about 15 days I've had it in my possesion a warning light came on with the sign "check adblue system". I filled the adblue tank with adblue but the light did not turn off. AdBlue is widely available from various outlets, including Citroën dealers. I know the link is for the berlingo van, but the same will apply to the facelift Berlingo Multispace when it arrives in the summer. Diesel technology is getting very complicated. Why cant Citroen bring out a decent petrol engine for the Berlingo Multispace? szo4LRD.