Installing Fuel Pressure Gauge

[84GNwith87eng]

Should this be done with the car on or off?

Any other tips?

 

[84BuickGNYorkPA]

Put fuel rail gage on, with the engine off. Read the gage to set pressure usally with the vacuum line off of regulator and the engine idling. Does this answer your question?

 

[84GNwith87eng]

Yep, just making sure it should be done w/ the engine off, I guess i was right