Fault code

Q I have a 2015 Citroën C4 Picasso 2.0 diesel (B78) with 244kms. The problem I’m having is the fault code P3049 - Correction of the quantity of fuel injected insufficient. I had this fault six months previous and checked wiring from ECU to all injectors including continuity, performed a leak-off test, removed four injectors and had them tested with cylinder 4 injector being faulty (failed on insulation test) so I replaced with a new one and renewed the fuel filter. Approx 4/5 weeks later I ended up replacing the remaining three injectors for the same fault/issue.

My question: is there anything else to check or could cause an injector to fail with 5-6000kms on it?

Thanks for your help.

Ray Boylan A The translation of the code P3049 is: Injector 4 - injector calibration. This would lead me to cover the same steps as you have already covered. Having dismissed the wiring from the ECU to the injector and having replaced the injector, I would next consider having the ECU tested. I did once encounter a similar problem on a Renault engine, and in this case the reason for the failure at such a low mileage was due to a fault within the ECU. This vehicle came to me after the owner was concerned that the injector fitted previously may have been of inferior quality. This was a fleet vehicle and the complete set of injectors had been fitted at the time, it turned out that the injectors were genuine units, and this had come at quite a high cost.

With the owner having spent such a large amount on the original repair, I was keen to ensure that no stone was left unturned while the vehicle was in my care, and this was one of the reasons that it was decided to look into the possibility of a faulty ECU.

This turned out to be the problem and the poor calibration from the ECU was the source of the issue. If another injector had been fitted without the ECU rectification, the vehicle I am sure would have been returned in a few more months with the same symptoms.