2010 Model Peugeot 308 CC 1.6 THP Consumes Excessive Fuel, I Request Urgent Assistance

[Altunsoy]

Hello, the car arrived recently. I don't know much about its characteristics, but it was in poor condition when it arrived. The engine was shaking, the exhaust was very inefficient, had a terrible, eye-sore smell, and the car had very poor power and traction. The car was burning about 20 liters of fuel per 75 km/h. Let me explain what I did to the car.

1. Original spark plugs replaced.
2. Upper Oxygen Lambda Sensor replaced with Bosch brand.
3. MAP sensor replaced.
4. PCV valve upper rocker cover replaced.
5. Smoke leak test performed for the intake manifold. No problems.
6. Turbocharger wastegate bushing replaced, and the wastegate was restored to working order.
7. Canister valve checked. I disconnected the power connector when the car was hesitant, but there was no improvement. When I tested it with Diagbox, I heard a ticking noise and it passed.
8. Engine water thermostat replaced.
9. The fan resistor was replaced.
10. The high-pressure fuel pump was overhauled. (It didn't report a fault, but it was still overhauled.)
After all this, the vibration and fuel consumption problems persisted.
11. I decided to replace the vehicle's timing chain and replaced it with the original tensioner, paddles, and chain. I've reset all the vehicle's learning data with Diagbox several times. The upper oxygen sensor data is around 1500 millivolts even with the ignition on, and the mixture always reads rich. I don't know what to do. I checked the wiring between the vehicle's engine control unit and the connector for the oxygen sensor. There's no problem; there's a signal. When I disconnected the Lambda oxygen sensor, it still shows 1500 mV in Diagbox. I'll attach a screenshot so you can see the latest readings. Please help. Thanks.

[Altunsoy]

[PaulC5]

Cylinder 3 seems to be different, please could you translate what it says.

[xantia_v6]

What engine fault codes are present?
Did you check the cylinder compression pressures?
Did you replace any ignition coils?
Can you remove the spark plugs and photograph the electrodes so that we can see the condition?

[Altunsoy]

Hi, let me answer both of your questions: Each cylinder performs individual injector adjustments. While I was taking the photo, I made an adjustment to the third cylinder's injector. You can see that at that moment, while the car is running, the others display some data at different times. There are no fault codes in the engine control unit. The car runs very stable after adjusting the timing, so I didn't even need to measure the compressor pressure. I also don't have a compressor gauge suitable for this vehicle. I didn't replace the ignition coils because they aren't showing any errors, and they appear to be in good condition. If there's another way I can check the coils, I'd appreciate it if you could tell me. I can't remove the spark plugs because I'm not with the car right now, but the spark plugs haven't even been driven 1,000 km. The original spark plugs are also the ones you know I added a catalyst additive to this car. I forgot to mention that, I think it was Rislone. It also cleaned the injectors. I'm re-uploading the image I uploaded using Translator. Thank you.

[Altunsoy]

Can someone please help?