Seat Toledo Diesel Stalling and Rough Idle

Rough idling and stalling can be a nightmare. I had a similar issue with my Toledo, though I can't remember the exact year. The engine misfire was driving me crazy! Have you checked the wiring harness and connections to the fuel injectors? I remember I had a bad connection there that caused intermittent problems. It might be worth a look before you start replacing parts.

Thanks for the tip! When you say 'bad connection,' what exactly do you mean? Was it visibly damaged, or did you have to test it with a multimeter? And which fuel injector specifically gave you trouble?

Yes, I mean a corroded and loose connection. Visually, it looked okay at first glance, but upon closer inspection, the connector was cracked, and there was some corrosion on the terminals. I didn't test with a multimeter initially; I just cleaned the contacts and tightened the connection, which solved the issue temporarily. However, the problem returned a few weeks later, so I ended up replacing the connector entirely. Given your symptoms, especially the stalling and rough idle, I'd strongly advise getting the fuel system checked professionally. A faulty fuel injector could also cause similar problems, but it's best to rule out the simpler things first.

It was indeed the fuel pressure sensor. The cable and plug looked corroded. Replaced it and now it runs like a dream. Cost me 95€ all in at the workshop. Thanks a lot for your help!