Hi awesome group of Japanese car lovers! As some of you are aware, I recently purchased a 2012 Vellfire 2.4ltr petrol. The car drives pretty decent for a 12 years old car. I have noticed something that bothers me and I don't know if it's in my head only or is real. When I am driving in manual, the issue doesn't appear. In Drive, when I drive around town/villages, the gearbox always tends to accelerate towards the point where it will change to the next gear. If I try to bearly touch the acceleration,  it will drop the RPM to around 1k-1.2k and it will start vibrating and making a squeaking noise outside of the car. As soon as I press the acc a bit harder, the rpm will increase and the noise+vibration are gone. The problem is that I cannot drive constantly at the same speed, I have to press the acc then remove my foot and so on. Before this car Ihad for 6 years a Prius and maybe I am not used with petrol cars, but I doubt it. Could it be something wrong with the gearbox? I remember that when I bouth the car, on the obd2 I had an error related to the angle of the throttle not being able to detect it, but the error is gone now. I have a video from today with the noise and the low rpm . How is your gearbox behaving when driving around town, below 50mph?

And this are the error codes that I still get! Any ideas plase?

I'm guessing based upon my general knowledge, but that error sounds like it knows what throttle position it is trying to achieve, but it either a: isn't happening or b: the position feedback for the throttle position (if it has such a thing) is defective. I'd be looking at the throttle stepper motor and throttle position sensors. I'd also guess that diagnostic software like techstream would be able to do a test function of both and it should be obvious whether the stepper motor is driving correctly. 

One extra thing, it is worth googling to see if there is a throttle position learning function for any Toyota that comes with your engine. It can sometimes fix these sort of problems and is often simple to do.  

Hi, a little update. I have purchased a preowned acceleration pedal with the throttle sensor, but the error is still there and the car is behaving as before. What else could it be?

On 4/29/2024 at 8:14 AM, Sorin said:

Hi, a little update. I have purchased a preowned acceleration pedal with the throttle sensor, but the error is still there and the car is behaving as before. What else could it be?

@Chris.ac please, do you know what other parts are in this circuit? Where else should I look?

2 hours ago, Sorin said:

@Chris.ac please, do you know what other parts are in this circuit? Where else should I look?

You have checked the throttle is working correctly? 

 

Use the diagnostics outlined here for the throttle and accelerator

 

http://zatonevkredit.ru/repair_manuals/viewdoc_html/AWI4O_qhU9h2CeTmduUr/AWI4PE8GrzlLPWuuVT0m

6 minutes ago, Chris.ac said:

You have checked the throttle is working correctly? 

 

Use the diagnostics outlined here for the throttle and accelerator

 

http://zatonevkredit.ru/repair_manuals/viewdoc_html/AWI4O_qhU9h2CeTmduUr/AWI4PE8GrzlLPWuuVT0m

Thank you Chris!

Hi Sorin

 

have you solved the issue?

how?

@Sorin I would be interested to know the answer to this problem as well. did you sort it? I know a year has gone by

Hi, I have not solve the issue, unfortunately.  More than this, I managed to overheat my engine by running it without coolant( a radiator leak) so I was forced to sell it.