Scenic Transmission Issues

Whoa, that sounds rough! I have a Scenic too, though I'm running a petrol engine. I had something vaguely similar happen a while back. The engine would surge randomly, almost like it was trying to take off on its own. No lights on the dash though, which is weird. Could be related to the lock-up clutch you mentioned maybe? Did you notice anything else happening around the same time?

The engine surge is interesting... I haven't specifically noticed that. The slipping is the most obvious thing. When you say 'vaguely similar', how long after the surging did you get it sorted? What was the diagnosis in the end?

Okay, so mine was a bit like a dodgy tap, dripping issues but never flooding. It went on for a couple of weeks – just little surges, nothing dramatic. Eventually, I took it to a workshop. They plugged it in and said it was a sensor on the transmission acting up, causing the converter to not lock up properly sometimes. Given your error code and the grinding, I reckon yours is more serious and needs proper workshop attention. Don't delay, you don't want to cause more damage!

Thanks for the info! Sounds like I'll be booking it in ASAP. The garage confirmed your suspicions – torque converter was toast. Ended up costing me 2120€ for the repair. Ouch!