I installed the Fass DDRP and had 18#-20# at idle and 13# wot. I now have about 500 miles on it and now the fuel pressure has dropped to around 16# at idle and around 13# wot. Cruising with full load (travel trailer) stays around 16#. When I was getting the higher fuel pressure the temperature was in the 90's and now with temperature around 70* I am getting lower readings, is this related to temperature or could there be something else wrong.

 

On my air dog when pressure drops(starts jumping around) its time to take spring that holds check ball(in return side of pump) in place out and give it a stretch have had to do this 2 times in 8,000 miles.It needs a stiffer spring I.M.O .Nate

 

Not sure if there is something wrong, I would call. But those pressures are still ok. FWIW - My fass (not DDRP) is around 16-17 Idle and drops to about 12-13 WOT. Cruising it stays right at 15.

Not sure about the Temp issue. Doesn't seem as though a 20* ambient temp would drop pressure that significantly. I think you fuel temp is gonna rise above that anyway. So I'm not so not sure it would have an affect. If your pressure changed while driving, that might give you an indication temperature was a major factor in the drop.

I'm not saying nothing is wrong, just saying you are ok till you get it figured out. But definitely call them. They will give you a process that you have to go through to determine the nature of the deficiency.

 

Call FASS. They have a good reputation for product and service. You don't need higher pressure, only to know that what you have will remain constant & not crap in the middle.

 

Does anybody know if Fass has a website or how to get a hold of them, all I can find are Fass dealers.

 

I would call the people you bought it from. They will get you headed in the right direction.