Nissan Kix reduced engine power

Sounds frustrating! I had a similar issue with my old BMW 3 series. Reduced power and a mysterious error code. Did the code reader give you any specific diagnostic code? Could be a number of things, but in my case, it was related to some dodgy chip tuning that a previous owner had installed.

Thanks for the reply! Yeah, it did throw up a code, something like P0606, Internal Control Module Processor. Dodgy chip tuning, eh? How did you figure that out? And what did it cost you to fix?

The code is definitely suspicious. I initially had the same thought as you and took it to the workshop, they used a better scan tool to have a look and confirmed the worst. Some aftermarket chips mess with the car computer settings. Basically, the tuning 'optimizes' performance, but sometimes pushes things too far, or is just plain badly installed. The garage suggested going back to stock ECU settings.

Alright, thanks a lot for the advice! I'll take it to a reputable workshop and get them to check the ECU. I was fearing the worst, but it seems like there's a clear path forward. Just got it back from the workshop, and you were spot on! Turns out it was some aftermarket chip tuning gone wrong. They reflashed the ECU back to the factory settings, and it's running like a champ again. Cost me 180€, but totally worth it for the peace of mind!