Looking for advice: Renault Avantime 2001 shows various symptoms - Possible mixture preparation error

Hey, I had a similar problem with my 2000 Mercedes-Benz E-Class. Seemed to be a faulty fuel pressure regulator. These symptoms, like the black smoke and the fluctuating engine power, sound pretty darn similar. The guys at the garage had to replace the fuel pressure regulator. It was definitely not a small job, but it wasn't the end of the world either. It was a bit time consuming, but afterwards my Benz ran smoothly again without any problems. Hope that helps you!

(Translated from German)

Hey, thanks for your reply and the suggestion about the fuel pressure regulator. Would you happen to remember how expensive that was when you had it fixed? And has anything else come up since then or is your Benz running more reliably now? That would be really good to know. Thanks to you!

(Translated from German)

Hey, of course I remember. I spent about €250 on repairing the fuel pressure regulator. But after my Benz had that visit to the mechanic, everything went smoothly. The mixture conditioning error that plagued me before has since been fixed and my car runs much more reliably now. So don't worry, you should feel similar once your Renault is fixed. Hope this helps!

(Translated from German)

Hey, thanks for the useful information! 250 sounds acceptable to me if it gets my Renault running reliably again. Your Benz ran smoothly again after the fuel pressure regulator was replaced, which gives me hope. Your experience has really helped me. I'll go to the garage tomorrow and ask them to have a look at it. Hopefully everything will run smoothly. Thanks again!

(Translated from German)