Navara Rough Engine Running

Hey there, I had a similar issue with my old BMW 320d a few years back. Rough running, check engine light, and some weird error code about fuel trim. In my case, it turned out to be a faulty injector. The 'reset quantity drift compensation' sounds like the ECU is trying to adjust for an injector that's not delivering the correct amount of fuel. Have you noticed any black smoke or a drop in fuel economy? It's kind of like when your eyesight starts to go blurry, and your brain tries to compensate, but eventually, you need glasses (or in this case, a new injector!).

Thanks for the reply! I haven't really noticed any black smoke, but the fuel economy might be a bit worse than usual, hard to say for sure. So, if it's an injector, is there anything I can check myself, or is this something that really needs a professional to diagnose? Like, is there a simple test I can do, similar to checking the tire pressure, or is it more complicated?

Honestly, diagnosing a fuel injector issue accurately usually requires specialized equipment. You could try listening to each injector with a stethoscope (or a long screwdriver as a makeshift version) to see if one sounds different from the others, but that's not very reliable. Injector testing involves measuring the fuel delivery rate and spray pattern, which is best done with a proper injector testing machine. I'd recommend taking it to a workshop. They can pinpoint the faulty injector and replace it. It's like trying to fix a watch with a hammer – you might get lucky, but you're more likely to break something else!

Thanks for the advice! I appreciate you sharing your experience. I took it to a mechanic, and you were right – it was a faulty injector. They replaced it, and the rough running is gone, and the check engine light is off. The total cost was 515€, which is a bit painful, but at least the Navara is running smoothly again. Thanks again!