Engine/Transmission (1998.5 - 2002) Fuel pressure gauge isolator

[Texas Diesel]

I have a friend that has to add antifreeze to his fuel pressure gauge isolator every couple of months.



So at the last antifreeze add session I asked where he thought the antifreeze was leaking to. He didnt know. I said obviously if it wasnt on the floor of the truck then the antifreeze must be seeping back into the fuel system when the FP is zero PSI.



I've read of several others who have to "top off" the isolator, where is your antifreeze going?

 

[Scrappy]

mine is the same way,I thought It was just the air in the line because I can't get it bled well enough. but what you are saying is a distinct possibility.

 

[RAMICATOR]

i had a guage zip tied to my mirror for a while, my pressure was always good, 13-15 at idle. when i got my guage and isolater, i got it installed and my pressure reads 6-8 at idle.



is it because i dont have enough fluid and have air in the line?.

 

[Jeff Knight]

We just removed my isolator after the gauge wasn't accurate. A fitting was bkoke for some time. When we went to hook the gauge back up is when we removed the isolator. We put a small brass shut off valve in line in case there is a leak. I have the in tank pump. My pressure is 9-10psi at idle. Jeff