Peugeot 406 Crankshaft Sensor Issue

The symptoms you describe could be linked to the crankshaft or camshaft sensors. A defective crankshaft sensor can indeed cause the issues you're experiencing, especially regarding timing. Have you checked for any error codes using an OBDII scanner? A misaligned timing chain could also trigger those symptoms.

Thanks for the reply. I don't have an OBDII scanner myself. How exactly would I check the timing chain? Is that something I can easily do myself, or is it better left to a professional?

Checking the timing chain requires specialized tools and knowledge. Without the proper equipment, you risk causing further damage. Considering the crankshaft to camshaft reference value concern, it is advisable to seek professional assistance to diagnose and resolve the issue. It's likely a defective crankshaft sensor.

Took it to a workshop, and you were right! The crankshaft sensor was defective. They replaced it, and the reference value is back to normal. Car runs like new now. The final bill was 340€ Thanks for your help!