2017 prius rough idle and TONS of codes, help!

The training procedure is used by the manufacturer.

Due to the dissimilar parameters of different equipment, which is reinstalled when the power is reset, certain values are set in the engine ECU.

At idle, the ECU adjusts the air and fuel consumption to optimal values.

The better they are adjusted, the fewer failures in further operation.

 

What RPM values do you consider high and what caused them?

Can you record engine parameters with some device or program?

 

I have noticed, after 12 volt battery disconnect, an unusual “rev up”, during the next 2~3 start-ups. I’d speculate the car is reestablishing some parameters.

It would seem a fairly common occurrence, for the car to have an interruption in 12 volt power, and as a consequence many would be running less than optimum?

I’m a little incredulous, I mean it could be, but to have a design that routinely leads to many vehicles running less than optimum, or polluting more, wouldn’t automotive regulators be more interested?

 

During operation, the throttle valve may become dirty, the rubbing parts may wear out mechanically, and the electrical parameters may also change.

The ECU records input data corrections to optimize operation taking into account age-related changes.

When the 12V power supply is reset, a number of ECUs reset the accumulated corrections.

Then they begin to accumulate again, adapting to the required task.

During the training of a new throttle valve, the task is to maintain idle speed within 1000 revolutions.

The revolutions float slightly higher, slightly lower, gradually approaching the specified value.

The conditions for supplying fuel and air are adjusted to the same value.

So that the engine does not stall and there is no excessive fuel consumption.

The ECU remembers the new values and uses them when working with this system.

Gets used to it. When a new valve is installed, the old habits do not work as desired and the process is repeated.

The throttle valve can self-learn during trips, but this takes longer.

The ECM INSTALLATION procedure has the same item:

7.PERFORM INITIALIZATION
Tech Tips
Initialization cannot be completed by only disconnecting and reconnecting the cable of the negative (-) battery terminal.

• Perform Initialization when replacing the ECM

 

This is a minimum setting, if it does not work, then something is not working correctly.
You need some kind of diagnostic device, an OBDII adapter with a phone, a laptop with the Techstream program, a diagnostic scanner.
It is impossible to determine errors by eye or by ear.
This will not bring quick results. Changing parts one by one is quite expensive, without understanding the reasons for the problem. A chance in a thousand that you will suddenly get lucky.

 

Understand that a good scanner is necessary for effective use and diagnostics.
Prius is a car stuffed with electronics. Many systems are interconnected. Incorrect operation of one system can indirectly affect another system.

For example, error P319000 indicates several problem areas and it must be solved correctly not by changing parts, but by finding out which system parameters do not work as they should.

Your scanner at best gives only a letter and a number of the code. This is not enough for diagnostics.

P319000 by MAX2 posted Mar 3, 2025 at 11:50 AM

 

Watching South Main Auto, the majority of his cases are electronics related, every current car on the road is thus I think.

 

Yes, there are many such cars now.
But Prius was the first almost thirty years ago, when it came into being. Many were innovations.