Infiniti G's Multiple Symptoms Point to Major Misfire Issue

Hey there! I had a somewhat similar experience with my 2015 Infiniti Q50 (not too far off from your G), and I have some experience working with cars, though I'm not a pro mechanic. When I had those exact symptoms rough running, power issues, and that nasty exhaust smell it turned out to be a faulty fuel injector. Took it to my regular workshop, and they diagnosed it pretty quickly. The fix involved replacing the defective injector, which set me back about 515 Euro, but it solved all those issues completely. What's your mileage on the G? And have you had any diagnostic codes read? That would help me tell if you're dealing with the same problem I had. Also, which engine variant do you have? The Infiniti line (both G and Q series) can be pretty similar in terms of these issues. Feel free to share more details, and I'll try to help based on what I learned from my experience!

Thanks for sharing your experience! My G is at 178492 KM and just had its service last month. I got the P0300 code read at a local shop, which points to unusual misfires, but they couldn't pinpoint the exact issue. Your fuel injector situation sounds really similar to what I'm experiencing. Did you notice any particular signs before it completely went bad? I might take it to the dealer this time since my regular mechanic seems stumped. Hopefully won't cost me an arm and a leg to fix!

Hey again! Yeah, I totally understand your concern about the P0300 code. With my Q50, I actually noticed some warning signs before the fuel injector completely failed. The car would occasionally hesitate when accelerating from a stop, especially when the engine was cold. I initially ignored it (big mistake!), thinking it was just normal wear and tear since my car had around 165,000 KM at the time. The symptoms you're describing are almost identical to what I experienced. When my fuel injector started failing, the unusual misfires drove me crazy it felt like the car was having problems, especially during acceleration. And that strong exhaust smell? Classic sign of unburned fuel, just like what I dealt with. Since you mentioned your regular mechanic is stumped, going to the dealer might be your best bet. Though they're usually more expensive, they have better diagnostic tools specifically for Infinitis. Just a heads up if it is the fuel injector like in my case, make sure they check all of them while they're at it. Sometimes when one goes bad, the others aren't far behind. Let me know what the dealer says! Fingers crossed it's something straightforward like my injector issue and not something more complex.

Thanks so much for all the detailed info! Really helpful to know about those early warning signs now that you mention it, I did notice some hesitation during cold starts over the past few months but didn't think much of it. Definitely won't ignore those kinds of signs in the future! I've scheduled an appointment with the dealer for next week. I'll make sure to ask them to check all the injectors like you suggested. Will probably cost more than my regular mechanic, but at least I might finally get this sorted out. Really appreciate you taking the time to share your experience it's given me a much better idea of what I might be dealing with. I'll update you once I hear back from the dealer!