Fuel Pressure issue

[seoul4korea]

So I have a Walbro fuel pump and I noticed lately that every once in a while when I turn the key to the ON position I'll here what sounds to be pressure venting (Almost like a loud puff sounds). When that happens it seems to take longer to start the car back up. I have normal AFRS and I don't notice any fuel cutting out or anything... any ideas?

 

[jdmfreak]

Is your fuel wiring stock? Iirc Your pump shouldn't turn on till you crank

 

[seoul4korea]

Is your fuel wiring stock? Iirc Your pump shouldn't turn on till you crank

It is stock wiring, I was always under the impression that it'll it gains power when switch to ON.... Am I wrong in thinking that?

 

[jdmfreak]

your fuel pump should stay off till you crank then it should continue to run with the engine

 

[seoul4korea]

your fuel pump should stay off till you crank then it should continue to run with the engine

Ok so well would you think would cause the issue i'm having then? I'm at a loss as to why it sounds like pressure is being vented when I switch to ON and also why it takes longer to start then.

 

[jdmfreak]

Can you have someone else turn the key while you listen for where the sound is coming from?

 

[seoul4korea]

Can you have someone else turn the key while you listen for where the sound is coming from?

Yes

 

[hvyman]

That is how a 7m is.

Most jz swaps the pump will run with the ignition on.

 

[jdmfreak]

That is how a 7m is.

Most jz swaps the pump will run with the ignition on.

Oh my bad... thanks for correcting me

 

[IJ.]

Very dangerous... I'd be wiring in a Propane safety switch.

 

[jdmfreak]

Very dangerous... I'd be wiring in a Propane safety switch.

Lol I was just about to post.... "isn't that dangerous?"

 

[seoul4korea]

Very dangerous... I'd be wiring in a Propane safety switch.

Details? I'm wondering how big of an issue it is. Also do you have thing on why it keeps venting?

 

[IJ.]

Propane cars run a safety switch that's RPM activated and will shut off the fuel flow if the engine dies, consider if you crash and rupture a fuel line but the IGN is still on you're pumping the contents of the tank into the crash scene... all it takes is one spark and instant crispy critter!

Only thing I can think of is the Charcoal Canister Purge fo9r the venting on start up.

 

[seoul4korea]

Propane cars run a safety switch that's RPM activated and will shut off the fuel flow if the engine dies, consider if you crash and rupture a fuel line but the IGN is still on you're pumping the contents of the tank into the crash scene... all it takes is one spark and instant crispy critter!

Only thing I can think of is the Charcoal Canister Purge fo9r the venting on start up.

Hmmm I mean I don't have a can in mine, I see what you mean. What if I wire in a toggle switch for the fuel pump?

 

[IJ.]

Hmmm I mean I don't have a can in mine, I see what you mean. What if I wire in a toggle switch for the fuel pump?

What if you're unconscious after an accident?

 

[OfnaRcR4]

What if you're unconscious after an accident?

There we go!

 

[seoul4korea]

What if you're unconscious after an accident?

Very valid point, well looks like ill have to do some research soon. Back on topic, any ideas about the pressure loss?

 

[IJ.]

Go have a look at my Datsun Z car thread... I was out of it for a long time...

You said you have no charcoal canister what else do you have or not have.. too hard to "guess" at this

 

[str8_6]

why don't you have the charcoal canister? I've always read that you should have that.

 

[seoul4korea]

why don't you have the charcoal canister? I've always read that you should have that.

smog stuff and my swap didn't come with one.