Presage Defective Injector

The symptoms you describe certainly point towards fuel injection issues, particularly with that error code. Rough running and a check engine light are classic signs. Given the code relates to 'quantity drift compensation', the ECU is likely struggling to properly adjust fuel delivery. Have you tried any onboard diagnostics to see if any specific injector is highlighted, before assuming they are all defective? Performance tuning and regular fuel injection maintenance can minimize these issues.

Thanks for the quick reply! I haven't run any specific diagnostics beyond reading the error code itself, to be honest. Is there a straightforward procedure for checking each injector individually without pulling them all out? I'm hoping to avoid disassembly if I can...

I understand your reluctance to start dismantling things unnecessarily. Unfortunately, without more detailed diagnostics focusing on individual injectors, a definitive diagnosis is difficult. Based on your description, the error code, and the symptoms, the likelihood of one or more defective injection valves/injectors is very high. Therefore, my suggestion is to have the issue professionally inspected and repaired by a qualified workshop. Attempting more in-depth diagnosis yourself without proper tools and expertise could exacerbate the problem.

Appreciate the advice; it’s what I suspected. I took it to a local shop, as you suggested. Turns out you were spot on – defective injector. Cost me 515€ to get it sorted, including the part and labour. Runs like a dream now, though!