2010 Prius still shakes after head gasket job and EGR + intake cleaning

There is no direct egr step position status or feedback. But the egr step test uses the map pressure as a good indicator.

A lot of this assumes your previous egr block test was successful. I would block the flow manually again and drive it 15 minutes in normal mode (not maintenance mode) and verify the engine runs good with a full warmup. If it does not continue to run smooth you have to reevaluate your focus.

Egr step test with Techstream

Run the egr step test procedure while watching the map pressure. The engine must be placed in maintenance mode to force continuous running. The procedure wants you to warm up the engine. You will see map pressures at idle changing as you command the egr open using Techstream.

When the egr is closed at step 0, the map pressure usually reads about 4 psi absolute. As the egr step opens the psi will increase causing idle roughness around step 15-20.

Later you should be able to watch the map pressure under normal conditions and significantly understand what the egr is doing. Remember, the egr should be closed at idle and low rpms. The egr valve is also closed at wide open throttle.

 

You can check the power and wiring continuity with a meter.

 

I'm not sure about using MAP under normal conditions for info on what EGR is doing, because under normal conditions the MAP is so strongly affected by throttle position and engine load that the effect of EGR will be hard to tease out.

The car does a self-test of its own for EGR, where it uses the MAP reading, but only at moments when the car is decelerating, the throttle is closed, and the engine is spinning without fuel. Under those specific conditions, it is able to interpret the MAP reading as a test for EGR.

The result from the last time the car ran that self-test can be viewed on any scan tool that can show "mode 6" results.

 

When I was researching EGR cooler cleaning threads, I would swear I saw a post where someone purchased a new EGR valve and had to also have an update flashed on their ECU.

When I did my cleaning two weeks ago, I purchased a used EGR cooler and valve from eBay. Cleaned the used components and swapped them in my 2013 Prius. Engine at the initial start ran rough and would die after a minute or so.

Compared the part numbers on the used valve vs the one I removed. Used part number ended in '10', the one I took off the car was the same, but ended in '20'.

Cleaned the '02' one I had removed and swapped it back into the engine. All was well and the engine ran fine.

Bad 'old' valve from eBay? Or something not compatible with my newer vehicle / ECU?

EGR valve from eBay - 25620-37110 (did not work correctly)
original EGR valve - 25620-37120 (worked when cleaned and reinstalled)

 

When you buy something like the egr valve used, you don't really know what you are getting.
The egr valve may have already been replace with the updated very and the ecu updated.
Using the older part caused issues....