Egr temperature in accessory mode, car on, engine off

I'll have to check Mama's car tomorrow she has a gen 3 but the EGR valve gets pretty close to exhaust gas hot which is very hot thousand degrees close to it 700 something

 

What are you touching the electric motor that's on the EGR valve assembly? I mean I guess that could get pretty hot just by running but I wouldn't think so. I mean the gas engine it's got to come on sometime so just sitting in the driveway with the car on like running the radio the EGR valve gets hot enough that you can't touch it? Wild

 

I'm walking out to a 2013 Prius persona and I'm going to ready the car and put on the radio the ice engine is going to come on at some point just because it will and we'll see should be back in about 10 minutes

 

Okay so I'm out at the persona now I get in the car push the brake hit the button before I can get out flip the hood latch the engine starts The engine runs about 40 seconds or so The EGR cooler is just beginning to get as warm as my body temperature is at that point the gas engine shuts off and the cars just sitting here making its normal humming noises The EGR cooler is still the same temperature the valve forward of it which is connected to the engine is of course not even warm yet as the engine's not even warm but the motor on the end of the EGR valve is warmer than all of it but not rising so it's like holding a solenoid open or something or doing something in that black part of the electric motor but it's not heading to alarmingly hot it seems to be about I don't know 105° maybe I'd have to get the temp done out but not hot enough to fry an egg on or anything like that not to move my hand My hand is resting on it.

 

Mine did not get hot enough to make me move my hand and I'm relatively heat sensitive so. But no I don't think so and if it does I would think there's something wrong inside of that cover which is what just the stator part or whatever anyway. So maybe there's a bunch of carbon filings in there or something that need to be got out or it's just run to ground or something.

 

Any answer to this?

 

The EGR valve doesn't have any position sensor, so the way the control module has any confidence about where "closed" is, is it just constantly sends steps in the "close" direction, whenever the valve ought to be closed. At least, according to the repair manual reference waveform, it sends them constantly if the engine is warm and idling.



Does it also send those pulses when the engine is stopped? It would seem an odd choice to me, but I don't know the answer. I do know the ECM keeps the pulse-modulating control of the throttle body active when the engine is stopped, and it does seem odd to me, but so help me that's the source of the whine that makes so many people say "what's this whine when my engine is stopped?".

So I'd be willing to believe the ECM is still sending pulses to the valve in the "close" direction, but I don't know it for a fact. Somebody could hook up a meter or 'scope and have the answer pretty quick.

 

I can not hook a meter or oscilloscope to these wires, but I am almost sure, after the ICE shuts off, the computer drivers the valve close twice and stops.
You can hear two clicks if you here to the EGR valve motor after the ICE shuts off itself.
These two clicks are the rotor knocking the stopping point twice.

If the EGR valve motor is very hot in accessory mode (ICE cold, not running), you could test it disconnecting the plug on the EGR valve motor and checking, if the part gets cooler.

Mat

 

It’s definitely brown?