Grandeur diesel water sensor issue

Oh, I feel your pain! I had something similar happen with my Grandeur. Same symptoms, check engine light and rough running. Have you checked the cable and plug connection to the sensor? That’s often the culprit. Sometimes those connections get corroded or loose, causing all sorts of weird electrical issues.

Thanks for the tip! When you say 'cable and plug connection', are we talking about the connector right at the sensor itself? Is there anything specific I should look for, besides corrosion? I'm not super familiar with auto electronics, so any pointers would be great.

Yes, I am referring to the connector directly at the sensor. Look closely for any signs of damage to the wires themselves, sometimes the insulation can crack or fray. If you're not comfortable messing with it, I'd strongly suggest taking it to a workshop. I did that, and it turned out to be exactly that cable issue. Cost me about 95€ to fix, but worth it to avoid further problems! A faulty water sensor can mess up the whole fuel injection system.

Thanks so much for the advice! I'll check the cable and plug connection at the sensor like you suggested, but if I don't see anything obvious, I'll probably just take it to a workshop. I appreciate you sharing your experience!