ACCELERATION PROBLEM

Hello Gurus in the house. Pls I need you guys to look at this graph of my MAF sensor if it’s out of calibration and underreporting. The only tool I have is the OBD2 Bluetooth.
The graph was captured with the car standing still and engine rev to the max 7000RPM while MAF reads between 46-48g/secs
I am also attaching the results of my exhaust gas readings maybe the problem is caused by my A/F wideband upstream sensor...pay attention to bank 1 sensor 1.
Car is Toyota Avensis Verso 2002
Thanks

What does it read at wide open throttle in 1st gear? Revving in park isn’t really a valid test. Get me intake air temp engine rpm maf g/s at the time. I’ll do a volumetric efficiency test on the sensor for you and let you know

Just curious what makes you think that it’s a MAF problem and not a fuel delivery problem or an exhaust restriction, or TPS?

John Curtis wrote: Just curious what makes you think that it’s a MAF problem and not a fuel delivery problem or an exhaust restriction, or TPS?

My suspicion is base on the fact that when I bought the Car I was advice on this forum to clean my MAF, which I did 3 times.
Before the cleaning of the MAF my short term fuel trim was -9, long term fuel trim around -20, and after cleaning of the MAF STFT -1.56 to -4.19, LTFT -7 to -10. The improper mixture of Air and Fuel is dumping fuel inside my catalytic converter making it give a clicking sound like an overheated metal. I have changed to another used CAT, detached Muffler, detached resonator and still the drivability problem didn’t go away, so I doubt this is an exhaust restriction. I have changed TPS also

I have attached screenshots showing all the data Cheryl requested to do a volumetric efficiency test for me.
Engine size 2.0L
IAT: 69.8 degrees Fahrenheit
RPM: 5026
MAF: 74g/s
Europe is all about part changing as the cost of labor to repair is high. I was giving a quotation to change PCM and CAT without any serious oscilloscopic investigation on the actual failing parts.

I follow mostly American channels for DIY videos.

Well I’m running the numbers and it’s coming out to 76%. Do you know your baro reading?? Also can you get us a shot of oxygen sensors during wide open throttle to see if it’s leaning out. Or what it’s doing

Baro is 1030 hPa or 1030 millibar and temp was 6 degrees Celsius.
I am attaching multiple data captured for 2 categories of tests.
1. Oxygen sensors tests
2. Fuel trims tests.

>>>Oxygen sensors tests will be pix 1,2,3. All the data you need are captured and circled in red on the right hand at various RPM (downstream sensors/ upstream sensors/ RPM&TPS)
B1S2 - Green
B2S2 - Orange
B1S1 - Blue
B2S1 - Yellow
RPM - Red
TPS - Turquoise

>>>Fuel trims tests will be pix 4,5. All the data you need are captured and circled in red on the right hand at various RPM (STFT&LTFT bank 1 / STFT&LTFT bank 2 / RPM & MAF)
STFT Bank 1 - Green
LTFT Bank 1 - Orange
STFT Bank 2 - Blue
LTFT Bank 2 - Yellow
RPM - Red
MAF - Turquoise

I couldn’t graph them separately, but I guess you can make something out of the joint graphs.

I have now fixed my 3yrs of acceleration problem. Two things I have done to make my car run smoothly.

1. Toyota dealership sold to me one wrong upstream air fuel ratio sensor bank 1 sensor 1. This mistake has caused me so much time and money wasted. This mistake set CAT codes P0420 and P0430, so before you gut that CAT double check other things are working correctly.
89467-42010. Wrong sensor bank 1 sensor 1
89467-44030 correct sensor bank 1 sensor 1.
They initially gave me a ridiculous bill to change my CAT a second time and also PCM. After installing the correct A/F sensor the drivability problem disappeared.

2. I put oil in all my 4 brake calipers to allow easy spinning of my tyres, this alone improved things by around 25% before installing the right sensor.

One lesson this has taught me is don’t be a part changer unless you are 150% sure.

Thank you guys and wish you all a lovely 2020.