iQuad Boost Readings Lower than Boost Gauge

[Dieselfuture]

6 hours ago, Cummins4life said:

So I’m going to call fass in the morning 

You may need to modify your return to tank spring like this, so the ball doesn't get jammed in it.

Picture is from the air dog but you get the idea

 

[Cronus577]

14 minutes ago, Dieselfuture said:

You may need to modify your return to tank spring like this, so the ball doesn't get jammed in it.

Picture is from the air dog but you get the idea

 

I figured FASS would have fixed it by now. I know they were sending people replacement balls to solve the issue for anyone who had it. mine bounces a little bit but not as much as OPs. Will have to pull mine and see how it is. 

[Cummins4life]

2 hours ago, Dieselfuture said:

You may need to modify your return to tank spring like this, so the ball doesn't get jammed in it.

Picture is from the air dog but you get the idea

 

Thanks I’ll need to check it I put the fass on the truck a year ago but never had any gauges till now. So it could have been like that from day one. I’ll pull it in to the shop at work and check it over. I haven’t smelt like diesel for a while haha then I’ll change the filters while I’m at it.

[6cyl$$pit]

Also try having a full tank of fuel. I have a vulcan draw straw and a Fass but my truck is picky below about 5/8 of a tank, sometimes closer to 3/4. Below that amount my FP gauge will bounce, above that its steady. While I think at those levels the gauge reads high but either way... I also used a ball valve on the return line, so I could adjust my FP a bit higher than stock. Just wanted to let you know in case you have the same issue. 

[Cummins4life]

So found the problem with my fass it was the ball and spring. But now at an idle it is a constant 23.5 to 24 and when I get on it only drops to 22.5 is that bad? I have a 1/4 tank and it’s off the sender not a draw straw 

Edited November 3, 2018 by Cummins4life

[dripley]

It woud be good to drop it. If it were mine i would set it at 15psi as a low pressure at WOT and let the high pressure fall where ever it falls. 

[Cummins4life]

I don’t think mines adjustable as far as I know

[Mopar1973Man]

To go lower you'll need to change springs. You can order fuel pressure springs from DAP for both AirDog and FASS. You'll want a 17 PSI spring. 

 

Mine I did the same thing and curled the end coil inwards and somehow made a high spot and the ball keeps rolling to the wall and hanging open and allowing the fuel pressure to fall randomly. This is something I need to fix this weekend as well. Try and tweak that tail back down just a weebit.

[Cummins4life]

Ok thanks I’ll try that. The pressure isn’t falling any more it’s like I just need a lighter spring so that it will open and return the fuel a 17psi 

[Cummins4life]

I ordered the spring will it hurt any thing to keep driving it until it gets to me on Friday?

[Cronus577]

2 hours ago, Cummins4life said:

I ordered the spring will it hurt any thing to keep driving it until it gets to me on Friday?

Won't hurt a thing, mine has been bouncing since I got it brand new 3 years ago