Black Smoke & Stalling: Infiniti EX Diesel Mystery

Hey there, I had very similar issues with my 2013 Infiniti FX diesel last year. The symptoms you're describing sound exactly like what I experienced the black smoke, poor performance, and fuel consumption problems were a nightmare. Took it to my trusted mechanic and turns out several fuel injector cables were damaged, plus one connector plug was completely corroded. The damaged cables were causing irregular fuel delivery to the injectors, which explained all those symptoms. I ended up having to get the wiring harness replaced and new connectors installed. It was a serious repair that took about two days to complete, but the car's been running perfectly since then. No more black smoke, power is back to normal, and fuel economy is much better. I can relate to that bad mechanic experience took me three different shops before finding someone who actually knew what they were doing with Infiniti diesels. If you're still looking for a mechanic, make sure they specifically have experience with these engines, as the fuel system is pretty complex. Hope this helps!

Thanks so much for sharing your experience sounds like you nailed exactly what I'm dealing with! Quick question though do you remember roughly how much the whole repair set you back? Also, has everything stayed running smoothly since then, or have you noticed any other issues pop up? I'm trying to get a sense of what I might be looking at cost-wise and whether this fix really solved everything long-term.

Hey again! Absolutely happy to help! Since I got it fixed at my mechanic, the car's been running like a dream. All those annoying fuel composition errors completely disappeared after they replaced the faulty cable and corroded plug. The total bill came to 95€ honestly, not as bad as I was expecting given how much trouble it was causing! I've put about 15,000 km on it since the repair and haven't had a single issue pop up. The black smoke is gone, power delivery is smooth, and my fuel economy is back to what it should be. Really glad I got it sorted when I did these things can get worse if you leave them too long. Best money I've spent on the car, to be honest. Just make sure you find a mechanic who knows their way around Infiniti diesels like I mentioned before it makes all the difference! Let me know if you need anything else!

Thanks a lot for all the details! You've actually given me some hope here. Just got back from my new mechanic today and you won't believe it it was exactly what you described! Had the same issue with the fuel injector cables and a corroded connector. The repair cost me a bit more, around 120 €, but honestly, I'm just relieved it's fixed. The test drive was amazing no more black smoke, engine's running smoothly, and the power's back to normal. The mechanic you recommended really knew his stuff way better than my last one who kept giving me the runaround. Can't tell you how much I appreciate you sharing your experience. Saved me from a lot more headaches and probably some serious money down the line. Will definitely keep an eye on the mileage and performance over the next few weeks, but so far, it's looking good! Thanks again for all your help!