maxgee

iTrader: (5)

Here's vid of fuel pressure gauge when I turn ignition on, than a couple secs after the prime, it drops. 2nd vid is when the car is on at idle, no pressure drop.

XtremeDime

iTrader: (16)

So it starts up and runs just fine?

maxgee

iTrader: (5)

Yep. Still a little concerned.

XtremeDime

iTrader: (16)

Maybe I just dont see what this has to do with a Hobbs switch? lol. It sounds like it may be a bad check valve, which is usually built into the pump. I could be wrong though...

Blownz28man

iTrader: (2)

I agree, sounds like a bad check in the fuel pump... Or leaking injector.

ta02zx10r

iTrader: (19)

if it's a leaking injector then you probably don't want to cycle the fuel pump via the key very much since it is leaking fuel into the cylinder each time.

4SFEDZ

iTrader: (6)

do u have a boost references regulator? mine was leaking fuel back thru the vacuum port, thus releasing pressure.

BlwnLs1GTO

iTrader: (12)

Mine does the same thing. I'm running 2 walbro's with a Y at both ends. It runs fine when it's running constant but as soon as the key is off, it bleeds down within a couple of seconds.
I never figured it out. Hope you do!

Blownz28man

iTrader: (2)

I was running a adjustable regulator on my procharger system. The return line for it was between the procharger and fender. It smashed it..spiked fuel pressure and blew the diaphram. But it was running pig rich. You could tell there was a problem though..sucking fuel throught the vac port..

cjmatt

iTrader: (4)

sounds like once the pump stops flowing, the fuelgoes past the the check valve and flows back to the tank. my a1000 does the same thing because i dont even have a check valve in the system

black98ws6ta

iTrader: (77)

Could be the regulator, check valve in one of the pumps, or a bad leak somewhere in the system. It is not a normal function of having two walbros with one on a hobbs.

fastcars95

iTrader: (9)

My car does the same thing. I was at my friends house last night and he still has fuel pressure. He had not started his car in weeks. Is this a camaro thing.

OUTLAWZ RACING

iTrader: (9)

Mine dose it but not as fast it takes about 5 mins to drain back. I would check and make sure the hose are clamp on the pumps and no holes in them. A leaky injector would foul a plug fast and cause a pop on start up. If u used a worm gear clamp ur wrong the bands hold better. Its bleeding fuel somewhere double check every thing.

SLOWWZ28

iTrader: (1)

I have the dual pump setup from lonnies and mine dose the same thing! If it was an injector you would probably know it, whatever cylinder was leaking down would miss after those multiple key on off bleed downs! Also I have seen hundreds of pumps that leak down due to the check valve in the pump and never cause a starting or drivability issue! So I say if it runs and starts ok don't worry about it.

AFASTYZFR1

iTrader: (55)

I have the aeromotive regulator and mine does the same thing. Mine does not leak fuel out of the vac port, but I did call them up and aeromotive told me it was designed not to hold fuel pressure (Supposed to keep fuel from getting hot in the rails).

My injectors don't leak either and my car has been like that for over a year with no issues. Just have to start it right after it primes, or re-prime it if I leave key on for awhile and loose prime.

Awake455

Ditto. Been running mine for a couple years. Gotta turn the key on and wait a second or two before trying to start it or it cranks for a few seconds more as the fuel psi builds.

maxgee

iTrader: (5)

guess seems to be the norm, had a buddy come over and i put a fuel guage on his - also dual walbros - and same scenario.
oh well

sujomatt

iTrader: (7)

was not running duals - just a single.. but mine did the same.. but mine ALSO would take 2 primes sometimes to build pressure... POS

ChevyChad

iTrader: (50)

This has nothing to do with dual pumps and a boost referenced activation switch. This has to do with the return line. The stock system does not have a return line. If you added a return line, did you put a check valve in it? Most aftermarket regulators only bleed off fuel pressure ABOVE the desired set point, they do not keep the fuel pressure built up. More than likely, the fuel is not going back thru the feed line due to a faulty pump or leaking into the cylinders from the injectors, its going back thru the return lines and back into the tank. Think about it.. Whats gonna stop it from doing so?

Mine has been like that for years with no problems. I thought about adding a check valve in the return line, but found it easier to just add a prime button that would activate my second pump which primes the lines. I thought that was a better option than cycling the key 3-4 times.

black98ws6ta

iTrader: (77)

I assumed he had a stock fuel system other then the dual walbros, based on one being on a hobbs switch and the stock fuel rails in the videos. Aftermarket regs are known for leaking down but the stock does not(very much anyways). Which is the reason I recommended what I did.