Fuel Pressure Sensor Orientation

[Pistou]

Hello,

I wish you all a merry Xmas !!

I've just installed yesterday the fuel pressure and I read weird values from 7 bars to close to zero... I'm wondering if fuel pressure sensor needs a specific orientation since my pump (DW65v) is all new ? it's horizontally placed right now.

Thanks

[ArT]

Hello,

Happy new Year

Orientation does not matter. Make sure that you do not have leak and air bubbles in pipes.
What reading and voltage do you have when you switch ignition on but engine is still off?

[Pistou]

I have 7 bars when cold and much lower when it's off but hot... With the fuel pressure regulator it should be 3 bars always. I don't get it...

Did you meet failing sensor?

Thanks

[ArT]

Yes but in such case sensor gives 0V output.

7 bar on cold and lower on engine off is fine - you have still pressure on fuel rail when you switch engine off.
Fuel pressure regulator is only on fuel rail and injectors - before regulator is higher pressure (= fuel pump pressure). Fuel pump can give up to 12 bars.