Check engine light came on and I pulled these two codes 1690-0522, looked them up, but dont really understand what they mean? I am holding 12psi fuel pressure.

 

This is what is is in the service manual.

P0522---Oil pressure voltage too low. Oil pressure sending unit (Sensor) voltage input below the minimum acceptable voltage.

P1690---Fuel injection pump CKP Sensor does not agree with ECM CKP Sensor. Problem in fuel sync signal. Possible injection pump timing problem. Low power, engine derated, or engine stops.

Hope this helps some.