Question about engine bogging

Can you give a little more detail about what the engine is doing exactly?

The Prius is throttle-by-wire. Your go pedal is nothing but an input to a computer. When you hold the brake and gas down, this is not like a normal car where the brakes are holding the car stopped and the gas pedal is moving the throttle. In a Prius, there is just a computer saying "hmm, brakes are on and go pedal pressed, owner must want to do battery force charging" and the computer controls the engine RPM for doing that.

 

What do mean by tune up?

How many miles on it?

 

Are you holding the go pedal part way down? All the way down? Moving it any?

Does the app show you the charging current in real time while you do this, or does it only give you some kind of report at the end?

 

I'm not sure I've ever done that in mine, so I couldn't say how mine acts under those conditions.

I've done force charges occasionally, but usually I'm watching the charge rate on a ScanGauge and only holding the go pedal part way down.

I'm pretty sure if you push it all the way down, the ECU will go for a higher engine RPM, but it will also limit the output to what the battery can handle. That might show up as the kind of hunting behavior you've described.

 

Dr Prius does state the engine will slow down and you have to let up and press both pedals several times until the charge percentage shows 100%. It does make noise on a level you are not used to especially with no road noise or radio to drown it out. Overall the P0A80 code is more definitive than the Dr Prius test.

 

My advice to you is to stop experimenting with this hi-tech hybrid vehicle, lest you want to cause yourself a headache. It has 223,000 miles and no maintenance history; I'd be treating this thing very carefully. Stop bouncing it off the rev limiter.

 

What model year does the video use? Was it a 2010-11, or was it 2012+?

I seem to remember that there was a programming change regarding simultaneous brake and gas pedal application with the 2012, as a response to the earlier Toyota Sudden Unintended Acceleration outbreak. The Prius was already better behaved in this situation than other Toyota models, but I was thinking that it still received some change compared to earlier model years.

Can others with better memory or documentation clarify this, or straighten out my memory?

 

I have run the Dr Prius tests on my 2012. The forced charging will bring it up to a minimal level just like if you were parked in Ready for long periods. Cycle the pedals and you get more forced charge. There is no practical purpose for forced charging outside the questionable utility of these tests if the hv battery is decent and the engine is not pinging on acceleration with low charge. On the other hand, if your battery is coding, the mpg is down and it discharges at a traffic light, the test may confirm what you don't want to know.