my problem is the fuel pressure on the additude is changing very rapidly. normally it is 12-14psi at idle, 8-9psi at cruising speeds, around 5psi at wot.yesterday on a trip it would change from 8-10 at idle 11-14psi at crusing speed and when i would get on it 11-23,29. it is a stock lift pump but has only 7000 miles on it but i know that that doesnt mean that it is not failing. im not sure if it is the lift pump or a bad gauge it the edge additude? any help with this issue is appreciation thanks.

 

Maybe air in the line causing that big of a fluctuation? That's really odd. Or could possibly be a bad sender.

 

yeah it is funny running along at 10psi then to 22psi then back to norrmal. how can i check for air in the line.

 

I would think you can just bleed the line where it meets the gauge and tighten it back down. I would keep a eye on it though. It could be the pump failing also from what i have read in another thread.

 

thanks for the info. i will do some more research till i can call the diesel shop in the morning.