I am making this question as an update to my previous question .
I am not sure if updating that question will draw attention to it or keep it buried in the sea of questions here, if it gets updated please merge the questions since this is an update but a one that brings a lot of questions.
Since I asked the last question and got no leads I bought a bluedriver OBD-II scan tool which brought up 5 trouble codes and a questionable live data values.
My car is a Lexus es300 made in 2002
As you can see, all the codes refer to a problem regarding one of the two A/F sensors in banks 1&2. using the live data feature and monitoring the long and short term fuel trim %, The long-term % at bank 1 was around
-7.0% to -0.8% and at bank 2 the long-term % was higher at
-7.8% to 4.7%. The short-term values are shown in the picture below. I am not sure if those values are good or not but I read somewhere that up tp 15% is normal but probably that's when the vehicle is moving?.
Now moving into the Mass Air Flow rate, it ranged from
0.46 g/s - 95.04 g/s , the lower value is when the vehicle was idle and the higher value being when the vehicle is idle at +7k rpm. My car is a Lexus es300 made in 2002 and it's rated for 210 bhp, and the car's MAF averages at 66 g/s at 7k rpm. I assume that my car should have a MAF of at least 160 g/s, maybe 140 g/s because it's old, But maxing at 95 g/s is a problem. the max value specified in the range above happened because of the sudden change in the rpm or so I assume. the MAF rate averages around 66 g/s.
Here you can see that the Lambda values for both banks is around 1.000 so nothing is bad in the ratio.
Now I suspect that this is an airflow problem because all this fiasco started happening around the time when I changed the air filter, I have cleaned the MAF sensor by scraping the dust and using brakes cleaner and let it dry for a while before taking those measurements, I know brakes cleaner isn't the best option but it works and the MAF sensor was very clean when I saw it although I didn't change it before. And cleaning the sensor didn't change anything apparently.
Now my question is, could all the Air fuel ratio sensor trouble codes be popping up because of a problem regarding the air flow into the engine? in the top rated solutions part of the report, the bluedriver scan tool suggests changing the A/F ratio sensor, but one of the top solutions for all the codes changing the MAF sensor is a top rated solution as well even the knock sensor had changing the MAF as one of the solutions. Could all of these problems be caused by a faulty airflow? the car has almost no power and I have to rev up the engine to 3.5k+ rpm to be able to drive at 100 km/h (60 mph) whereas before this problem driving at 120 km/h was requiring an rpm of 2.1k.