Nissan 370Z reduced engine power

Sounds like a pain, especially with the Z. Reduced power and CEL definitely point to something funky with the throttle. From what I've seen, sometimes it's a simple sensor issue causing the ECU to freak out. Have you noticed any weird idling or hesitation, apart from the power loss? Could be a misreading in the air flow, messing with the fuel efficiency. Has the car gone into limp mode at all? Figuring that out may help narrow it down.

Yes, sometimes the car has a response delay when accelerating from a stop. I haven't paid close enough attention if there is rough idling. You mentioned a sensor issue, could you please elaborate on what specific sensor can cause this?

Okay, so that response delay kinda confirms it even more. I had a similar thing happen on my old Maxima back in the day, turned out to be a dodgy throttle position sensor. It feeds info to the ECU about how much you're pressing the accelerator. When that goes haywire, the computer gets confused and limits power to protect the engine. It's best to get it checked and replaced. Unfortunately, it might not be cheap. I’d suggest finding a reputable workshop or Nissan specialist to diagnose it properly. That way you minimize the chances of misdiagnosis and unnecessary expenses. Considering the symptoms, the ultimate repair cost could be around 265€, including the sensor replacement and diagnostics.

I took it to my mechanic, and indeed, the accelerator pedal module electronics were defective. Your diagnosis was spot on! After replacement, the car is running smoothly again. The final cost was about 265€, which includes diagnostics and labor. Thanks!