When the car is at 40km/h on speedometer the car jerks?

Hi Ken,
Please read my earlier post.
I would like to give as many details I can for you to get a better understanding of the problem I am facing since 3 months.
The car is a Toyota Corolla 2016 CE Trim with the 2ZR-FE engine. 1.8 L.( Canadian).
Its a 4 speed automatic and NOT a CVT.
Its similar version is in USA but comes with the L trim.
After getting this car I have done the following since I did not have the past owner maintenance record.
1. Changed Spark plugs
2. Changed PCV valve
3. Changed Engine oil/ filter
4. Changed Engine Air flow filter.
5. Cleaned the MAF sensor
6. Replaced the battery since no label on battery when it was purchased.
7. Changed cabin air filter.
8. Cleaned the intake valve area.
9. Cleaned throttle body area.
10. Changed transmission fluid through the return radiator cooling line with around 12 quarts used in total as the fluid was dark but not burnt. Did not drop the pan. Just put in Seaform Trans Tune after changing the trans fluid.
11. Cleaned the entire front ABS speed sensors both sides which was fully rusted and cleaned the gears in the hole.
The rear side I cannot do as the Abs speed sensors are located deep inside the hub.
12. Did entire underbody rust proofing as the car was really poorly kept by the previous owner.
13. Changed the coolant since reservoir was very low and no idea whether it was ever replaced.
I have a OBDII from Innova but it can only detect engine codes etc and till date no codes.

Transmission was checked at Toyota but they say no DTC.

Could you also recommend a OBD II that will detect trans codes as I got in a Autel AL 629 which says it is suitable for trans code reading but did not work on my 2016 Corolla. I had to return it.

Do you think any trans sensor could be the culprit since the speed suddenly increases on lower gears without pushing the gas and the vehicle speed downhill will increase quickly especially in the 40km/hr and 30 km/hr mark on speedometer.

THE car is absolutely fine on highways at 100 km/r and the rpm is below 3000 at this speed.
ON idle the RPM is between 600-900 range.
Also could you send me the diagram of the 2ZR-FE ( Transmission sensor locations )
I know all the sensors related to the 2ZR-FE Engine.

Previously I owned a 2005 corolla and never faced this issue.
Regards,
George

I will get back on this issue.

Hi Ken,
Could you give your valuable insight in this issue.
I took the car to a Toyota dealership.
I reported the same issue I have posted above.
They did a check and told me that no DTC codes are found and they cannot replicate the issue after a test drive and OBD check on Tech stream for trans
They charged me CAD 97 for the same. I insisted on getting the diagnostic report. They did provide.
I noticed that Engine and ECT has an update available but when I spoke with the technician he told me that since no DTC is shown he has not updated the Engiine and ECT.
What is your opinion? Did the dealership lie to me knowing this update would fix my problem.
Please give your opinion.

TIA

Hi Ken.
The problem is still not resolved.
1. I went to the dealer again and asked them why when a Engine & ECT calibration update is available why did they not update my car.
The answer from the technician was P2610- ECM/PCM Engine off timer performance code was not present hence he did not update.
What would you suggest here? Should I force them to do the update?
2. I changed the transmission revolution sensor but after driving for 2 days still the problem persists.
3. I ordered a carfax report wherein I found that the used car dealership had changed the front wheel bearings/Hub.
I am not sure of this.
In your earlier post you mentioned CV axle binding up issue.
Could you throw some light on this as to what to do before I move further.
TIA