Misfiring problem

My car is a 2009 1.6 diesel Manual Peugeot 308. My problem is that the engine of the car is getting louder and when I give gas in 1st and 2nd gear it misfires 2-3 times and then when I fully press the gas it cuts off. Another problem is that the fuel consumption of the car suddenly increased to 7.2 liters while it was 5.6 liters on average. I have gone to many mechanics and they connect it to the computer and say there is no problem. If anyone knows, please help. Mkldrsn2023-12-26 18:20:39

Seasonal conditions and fuel values can vary, and when it comes to misfires, have your engine bay checked. Best regards, good forums.

We just changed the engine mount. It's not a harsh knock, it's a gentle knock. It increased when the fuel problem started. It was like this in the summer too.

It seems like it is cutting gas. There are definitely people who can give detailed and in-depth information about this issue on the forum. Good luck, I hope you can solve it. Have a good forum.