ok so today i finally got my guages in and when i started my truck i noticed my fuel pressure is about 8psi at idle and drops to about 5psi at WOT. what kind of pressure should i be lookin at?

i have got an isspro mech fuel guage. i tapped in on the banjo bolt on the fuel filter housing, and have an isolater hooked up (thats what the kit came with).
all input appreciated

 

come onguys. im sure some of you guys have some input.

 

You are fine but you don't want it to go below 5psi. Start saving for a new fuel system, either LP or Air dog or Fass , or like me just a Holley blue pusher with a big line kit.

 

yeah thats what i was thinkin. i was thinkin about getting the walbro GFS kit and a big line kit from glacier diesel.

would that be a decent setup? what you all think about the BD lift pump kit?

 

Now you have the: Is it the " Isolator " or the LP question ?????
Probably the LP, but you could have air in the lines

Air in the line may make it read low, If the pressure builds
a little as you drive , you might have air in gage line..

Does the Fuel pressure Kick up when key is turned to Ignition.
If not , may be indication of Air or low isolator fluid...

Is it easy to bypass the Isolator to verify the LP is Low,???


What you are experiencing is why some of us chose direct reading gage.
Did not want Another component to trouble shoot....

 

Take a close look at the Air Dog set up that has banners on this site. Nice system and IMO better than the Glacier. It does more than just pump.
On the other hand we had a chapter member that bought the Pro Comp Black off Ebay for $50 and installed it. So far work great 14psi idle 10psi WOT. That's with the big line kit and no LP.
I'm running the Holley Blue and still using the LP. I have 27psi idle and 25 WOT.
If this fails i will probably get the Air Dog system.

 

I got the airdog and run 24-20 psi read at the pumps 1/8in pipe fitting. was getting 10.5 to about 7 fluctuation on the stock pump and changed b4 I did damage or got stuck. ED

 

Jturs,
I just did the Walbro pump and love it. Can't hear it run and it stays right around 18psi. Just wish I'd have done it sooner. I went through three factory pumps before I switched over.

Brad

 

when i turnt he ignition on i dont get a reading on the guage. so maybe it is low on fluid or air in the system. the insrtuctions said nothing about fillin the line so i only filled the isolater. dont really know how i could fill the line anyway.




i was actually looking at the airdog setup. i want to go FASS but i am on a tight budget. on vulcan a 95 FASS pump kit is 426.$ i believe. would i 95 pump be enough?i have plans for some mach 3's or 4's and probally a S300G turbo. oh and wouldnt 27psi at idle make for hard starts?

 

No hard starts for me. My Holley is triggered off a relay controlled by the stock LP.
For only $75 more you can get the whole system not just a pump.

 

Is there a fuel line to the Isolator ,( vs direct VP mount ) if so,
Idle the engine and crack the fuel line at the isolator, let some fuel out.

As for the gage side, you need help from the 'isolator ' experts

The line needs to be FULL from my reading here...

 

how much was tha holley? what are you comparing the price to? sry i lost ya.



ok so i just tried everything to try to bleed the guage side of the isolater. anyone have a good way of doing this.
i havnt tried the fuel side. iw ill try that right now. yes i have the fuel line from the fuel filter housing to the isolator.

 

Where did you buy the kit? If you got it from Vulcan performance i am familiar with that isolator and can at least give you some suggestions which may help solve your problem. Your lift pump could be bad also. I installed one on my buddy's rig and it had zero (0) pressure and would not even start after I installed it. He thought I was giving him a big line about checking his fuel pressure for the last several years. He's a believer now.

 

the Holley's are usually about $150 but a couple guys in my chapter have gotten the Pro Comp Black off Ebay for about $50. They work just the same and look just like the Holley. Probably come from the same manufacturer.

 

Originally Posted by scottsjeeprolet
No hard starts for me. My Holley is triggered off a relay controlled by the stock LP.
For only $75 more you can get the whole AIR DOG system not just a pump.

wow i read right over that. haha my bad

i got the kit from diesel manor.
i believe my lift pump has around 25k on it.
ok so i just bled the diesel side of the isolator and fuel pressure didnt change.
i tried to bleed the guage side again and i had coolant coming out and now my idle is 7 maybe 8 psi instead of 10 when i first installed it.