C4 Spacetourer deNOX error after cam-chain recall

[DanishBacon]

Hi guys.

I've just had my C4 ST (2022, 90.000 miles, 1.5 BlueHDI) have a new cam chain due to a full recall here in Denmark - at the same time the dealer changed the oil and updated the ECU, as part of the recall.

Now the car throws a P20EE about every 350 km (around 220 miles) and immediately flashes a "Start not possbile" together with an emmision fault and engine fault.

Have any of you had the same experience after the cam chain recall or a recent ECU firmware update?

[mickthemaverick]

Take it straight back to the dealer and get them to sort it!

[DanishBacon]

Agreed - but this dealer is a right pain and not willing to accept any responsibility. His first attempt at a fix was to suggest a new DPF for a measly 2800 pounds - due to high differential pressure according to him.

This lead me to buy a Lexia 3 and Diagbox - and no - the pressure is not abnormal and gets back to 5-6 mBar at idle and <40 at 3000 RPM after a normal passive regen.

So just asking here to see if any one else has been hit by what I assume is a firmware bug, since there is no count down associated with the "Start not possible" message

[BarneyRubble]

Here's a video on the same trouble code..

"P20EE SCR NOx Catalyst Efficiency Below Threshold Adblue Urea Flashing"

"This Peugeot Partner / Rifter van had flashing urea symbol light with 500 miles left before engine won't re start
nox exceedance is caused when the adblue isn't spraying correctly into the catalyst so a block adblue Injector is a common fault. it is also common for the adblue tank to fail"

The solution (in this case, for this code) is to clean the soot out of the urea injector and reset the NOx injector as shown in the video.

Everything I've learned about DPFs has come from watching 100s of O'Rileys Autos videos, so I can say your DPF analysis is spot on. Pressures are correct and the pressure sensor is working. A new DPF would make zero difference as that's not the problem.

Good luck! HTH!

[DanishBacon]

Thank you for the link. That Oriley guy is a goldmine!!!

I'll give the injector a clean and see if it helps.