Thought this might be helpful for some of the newer owners.

I did all these to the SSV

Cleaned the valve to shiny new
the valve moved freely by hand prior to and after cleaning
Watched it cycle itself correctly
Tested actuator with pump successfully
tested solenoids successfully
Swapped solenoids twice to see if code changed - it did not
changed all vacuum lines

And still ssv stuck open code.

last thing to do was test the impact switch, and sure enough it was DEAD. and I mean 0 ohms dead. I tested the impact switch plug with an ohm-meter. I somehow managed to grab the ssv plug by hand, unplug it, and test it without taking anything out of the way. I was also able to press in the impact switch when testing. A few scratches on the hand no big deal. The impact switch should produce 2 to 3 ohms when pressed in and 0 when not. So I tested mine and it read 0 ohms when pressed in. There it is, impact switch failure tripping my p2070 code because the computer thinks it's stuck open when it's not.

 

I've bought a used impact switch but it's only reading 0.4 to 0.6 ohms, is it worth installing it is it not enough resistance?

 

I'm not really any sort of professional, but it looks like a pain to install. If the SSV works fine and the sensor is all that's bad, perhaps it's possible to just live with the code... IDK. My SSV got stuck open the other day so I'm trying to figure that out.