I wouldnt just start replacing parts yet.
Pull the one wire plug to spool solenoid ( so it is not connected to ECU wiring )and measure with ohm meter to ground. It should be about 15 ohms. You can also run 12 volts to it and see if it clicks. This will prove your solenoid is good.
On the green plug(pressure sensor) bring up to operating temp and measure resistance across the the pins and you should get anything other than open.
You might need to check your pinout from ECU next then make sure you are getting oil.