Peugeot 407 Automatic Transmission Issue

Whoa, sounds rough! I had similar craziness with my 407. Was yours also acting up specifically when you put it in park? Mine was doing all sorts of weird stuff – hard starts, warning lights, the whole shebang. Did you notice if it was worse when the car was cold, or was it just totally random?

Thanks for the reply! Yeah, it seems to be park-related, but honestly, it's so erratic that it's hard to nail down. Cold or hot, it doesn't seem to matter. Was yours diagnosed as a control unit issue then? And if you don't mind me asking, what was the damage to your wallet?

Yep, control unit was the culprit! Honestly, after chasing my tail for ages trying to figure it out, I just bit the bullet and took it to a workshop. They ran diagnostics and confirmed it pretty quickly. Prepare yourself though – it wasn't cheap. From what you're describing, it's probably best to get it checked out properly before something else goes bang.

Thanks, really appreciate the heads-up. Sounds like I'm heading for a workshop visit. I suspected it was going to be pricey. Just got the diagnosis: defective control unit and a bill for 1000€. Thanks again for confirming my fears!