Renault Captur 0.9 Tce gasoline extremely high consumption.

Since 2016 it’s a 2nd car to buy a Renault Captur 0.9 Tce petrol. I and my wife are 55 and 54 years old and very moderate driver. The consumption of the Captur 8.0 l in the ECo overland without significant climbs. Highway at 135, over 10 liters consumption as well in the hill country. Km stand 52,000 km. We drive now with 2.8 bar tire pressure. Renault directly I don’t want to contact any more, so far only condescending answers. My question if the exhaust values are in Ordung, the tank has no leak…. where does the gasoline come in, don’t even dare to sell us the car because we are afraid that the buyer could complain later. For daily use we drive with a 10 year old Twintop of Opel. Petrol, which has a consumption of 6.5. 1985 to 1987 I had a Porsche 924, which has a similar high consumption. Besides, we are very dissatisfied with processing. ROSTIGE rims and brake drums as well as rusty AHK. ect. was already in the 2nd year. folding, pipe with heating. It can’s no consumption. We don’t mention the weather.