Peugeot RCZ Crankshaft Sensor Issue

Whoa, that sounds rough! Reduced power and worse fuel economy? That's the opposite of what you want from a diesel RCZ! I've heard whispers about similar problems, usually when the crank sensor is starting to fail. Is the engine idling rough, too? You mentioned the timing chain...those things are supposed to last, but you never know. Did you check the sensor wiring? Maybe it's just a loose connection causing the weird readings?

Thanks, the crank sensor idea makes sense. I did a visual inspection of the sensor wiring, but what parameters should I check to rule out a connection issue?

You did a visual check already...good. Honestly, without the right tools (multimeter and wiring diagrams), it's tough to be 100% sure. You're chasing a ghost, kinda. Bad wiring or a bad sensor will throw the same code. If it was my car, I'd probably bite the bullet and take it to a trusted workshop. They can properly diagnose the crank/cam sensor signals and wiring. Could save you time and money in the long run!

I decided to take it to a workshop for a diagnostic assessment. It turned out the crankshaft sensor was defective. The repair cost, including parts and labor, was 340€. Thanks for the help; your guidance was invaluable.