I had a fuel pressure gauge installed on my 99 dodge diesel. Should it show in the red when I get on it? And what should the pressure be? Thanks.

 

when your running high RPM's and your getting on it, as long as you have some pressure you will be ok. 4psi would be worring to me with the VP44.

where is the gage installed, on the lid of the fuel filter, or on the line before the VP44?