Peugeot 508 Injection Nozzle Defect

Those symptoms definitely point to a fuel delivery issue, and a dirty or faulty injector is a prime suspect. Have you tried any diagnostic procedures, like checking the spray pattern or resistance of the injectors? A simple multimeter test can sometimes reveal a dead injector, but it won't tell you if it's just clogged. Have you ruled out other possibilities like a vacuum leak or faulty mass airflow (MAF) sensor?

I haven't performed comprehensive diagnostic procedures beyond visual inspection. Could you elaborate on the recommended procedure for checking the spray pattern and resistance for a novice, particularly concerning the safe handling of fuel and electrical components? Also, how could a vacuum leak be related, and how do I identify and diagnose it?

Testing injector spray patterns usually involves removing the injectors and firing them outside the engine, which is messy and risky without the right equipment. Measuring resistance is safer; you're looking for a significant difference between injectors, which would indicate a faulty coil. Vacuum leaks can lean out the fuel mixture, causing similar symptoms to a fuel delivery problem. A smoke test is the best way to find them, but without specialized tools, it's tough to DIY. Given the mileage and symptoms, I'd strongly suggest having a qualified technician diagnose the issue properly. They can perform more thorough tests and pinpoint the exact problem. Could save you money and frustration in the long run.

After further consideration and acknowledging my limitations, I decided to consult a qualified technician. The diagnosis confirmed the injection nozzles were indeed defective, likely due to accumulated deposits. The repair involved replacing all four injectors, with a total cost of 515€. Thanks for your assistance in clarifying the potential causes and recommending a professional assessment; it ultimately led to an efficient and effective resolution.