AOA all members
Recently I purchased a swapped-engine 2006 Toyota Belta 1.3 2szfe with a CVT transmission. But the issue I am facing is that the mileage of my car is reduced at a very low range. The car is giving 9 Km/L with very soft foot within Lahore city. And with the normal foot, it gives less than 8. The condition of the engine is fine and not creating sounds o r has no oil consumption issues. Overall, the engine is working properly. I also scanned and thought to replace the o2 sensor and changed it with B1S2. But the issue still persists. Fuel Trim values are within the mark as LTFT 0% and STFT -1.56 to 1.56% at idle speed. And during a drive at approx 1500rpm values increased.
A have also done these actions but the mileage of my car is still the same.
1 Changed Engine oil to Koyama 5W 30.
2 Cleaned injectors and afterwards changed them.
3 Cleaned the MAF sensor and afterwards replaced it.
4 Got cleaned Catalytic converter.
5 Replaced O2 sensor 2 post Cat
6 Set tyre pressure to 30 psi.
I am working in industrial electronics as an electrical engineer. I purchased an Elm327/Bluetooth OBDii scanner for my DIY and made a screen capture video during the drive with selected display values of Engine RPM, O2S1, O2S2, LTFT and STFT. Actually, I wanted to attach the video here but I can’t. I can provide a link to the video here after uploading on YouTube. I think about the sensor values and still have doubt about it my 02 sensor values are O2S1 oscillating From 0.1 to 0.8 but approx 80% remain in rich values and 20% in Lean. 02S2 is behaving oddly on start its value rise slowly from 0 to 0.8 but most of the time it does not oscillate and keeps values above 0.6 V but in deceleration, it rapidly goes to 0V. I have replaced the sensors three times with 3 times and still the results have not changed. My friend also has the same car, and when I compared these values with his car, the values were the same but the mileage of his car was about 14km/l. I am not getting the right direction to fix this issue. Please help me to resolve the issue to get rid of this crucial situation. Kindly tell me the reason why is this actually happening as well.
Previously, the owner of my car installed 185/65 R15 tyres, as oversized tyres are also a big reason to reduce mileage but I searched on Google and I found it can affect 1 to 2 Km/l but not this much.
The pickup of my car is very good. And it can run from 0km to 60km/h quickly. But I also have a doubt the CVT gear of my car jerks when I drive the car at a very slow speed below 20 Km/h and the gear seems to slip in full throttle.