So, I am getting a P0090 and only a P0090. No other codes.
From research it looks like it could be one or more of the following.. https://www.ifixit.com/Answers/View/188773/mil+on,+dtc+P0090,+whats+that
1) PRC solenoid valve malfunction
2) Connector or terminal malfunction
3) Short to ground in wiring between PRC solenoid valve terminal B and PCM terminal 95
4) Open circuit in wiring between main relay terminal D and PRC solenoid valve terminal A
5) Open circuit in wiring between PRC solenoid valve terminal B and PCM terminal 95
6) Short to power circuit between PRC solenoid valve terminal B and PCM terminal 95
7) PCM malfunction
All my wiring looks good. So, I don't think it is wiring. That leaves #1 and #7.
So, what is the PRC Solenoid valve? Is it this part?
http://www.partsgeek.com/catalog/2003/mazda/protege5/fuel_injection/fuel_pressure_regulator.html
From research it looks like it could be one or more of the following.. https://www.ifixit.com/Answers/View/188773/mil+on,+dtc+P0090,+whats+that
1) PRC solenoid valve malfunction
2) Connector or terminal malfunction
3) Short to ground in wiring between PRC solenoid valve terminal B and PCM terminal 95
4) Open circuit in wiring between main relay terminal D and PRC solenoid valve terminal A
5) Open circuit in wiring between PRC solenoid valve terminal B and PCM terminal 95
6) Short to power circuit between PRC solenoid valve terminal B and PCM terminal 95
7) PCM malfunction
All my wiring looks good. So, I don't think it is wiring. That leaves #1 and #7.
So, what is the PRC Solenoid valve? Is it this part?
http://www.partsgeek.com/catalog/2003/mazda/protege5/fuel_injection/fuel_pressure_regulator.html