Sprockets

iTrader: (6)

I have a Walbro 255lph hp pump and an AEM fpr with the silver orifice installed. Fuel pressure at idle with the vacuum hose removed and pinched holds steady at 47psi. I have a Greddy blue box and the car seems slower at wide open throttle. Hopefully this is just a tuning issue that can be fixed with Hondata. It's weird, if I nail it to the floor in 2nd gear it's not as quick as when I ease into boost. Anyway, a couple things I've noticed: When taking the gas cap off, I no longer hear the pressure being released. I popped the hood to check for leaks on my new fuel pressure gauge (ditched the B&M for a liquid filled Marshall) while the turbo timer was counting down. No leaks, but I noticed that when the engine shut off the pressure dropped to zero pretty fast. Before I remember the pressure holding for a while, even with the larger gold AEM orifice. When I installed the Walbro, it's possible I over tightened the bolts. Would this cause a pressure loss due to the gasket being deformed? The gas cap also seems to come off easier. Maybe the gas cap needs to be replaced, I don't know. Any ideas?

Sprockets

iTrader: (6)

Can anyone help?

RH+G

see if you can borrow someone else cap first then check the pump. Sounds like a gas cap though

Sprockets

iTrader: (6)

Thanks man, I'll try that first.

Tiamat-blue

Just curious. Did you figure it out? I have the same problem after installing a jrsc. Kinda annoying to have to crank the engine a while to get it started cause the fuel's out of the lines.

raene

Mine has always done that after switching to a Walbro 190lph pump too... same with my brother's Walbro 190lph pump also. I don't think it's a problem with the gas cap.

Sprockets

iTrader: (6)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tiamat-blue &raquo;</TD></TR><TR><TD CLASS="quote">Just curious. Did you figure it out? I have the same problem after installing a jrsc. Kinda annoying to have to crank the engine a while to get it started cause the fuel's out of the lines.</TD></TR></TABLE>

I didn't figure it out, but I'll be placing a Honda parts order soon, and maybe I'll get the gas cap. I doubt that's the problem.

raene, since this happened to you as well, do you think it has anything to do with not getting a new gasket when installing a fuel pump? Or maybe like I said before overtightening?

I wish I saved the link, but there is some kind of dye you can put in your gas tank which can be used with a black light to detect fuel leaks. I wonder if it picks up vapors? I need to just take my seat off and see if there is a gas smell.

Tiamat-blue

Is it possible that we got air in the line? How would you bleed the fuel line?

EE_Chris

There exists a check valve in the stock fuel pump which holds pressure in the line after it has stopped running.

The Walbro probably doesn't have it....no big.

PM-Performance

mine held pressure nice with my last guage, thne i got a new one and noticed the sdame thing now , i dont strees it much , i know theres not leaks and the car runs strong as ever, so i ignore it

88_SC_CRX_Si

Dropping pressure can be mostly caused by:

The check valve, like mentioned above.
Leaking injector(s)
Leaking FPR

raene

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by The Dude &raquo;</TD></TR><TR><TD CLASS="quote">
raene, since this happened to you as well, do you think it has anything to do with not getting a new gasket when installing a fuel pump? Or maybe like I said before overtightening?</TD></TR></TABLE>

It might have something to do with this, yes... also that annoying gas vapour smell is probably due to a bad gasket on the fuel pump mount where it bolts to the tank. But like others said I think it's mainly a missing check valve or something in the pump. I don't sweat it much since the car runs fine and it usually builds pressure fast enough after switching the car on for a moment that it doesn't shudder on startup .

foesicks

Same problem I have after installing a Sard regulator with an lines. When you turn the car on pressures up for a few seconds then drops right after the fuel pump turns off. Vacuum dose nothing when you unhook it, fuel psi stays the same just as it dose with + positive pressure i.e aircompressor. Oh yeah car is also a bitch to start. The regulator held pressure on my brothers car, work fine on his car then he went to an aeromotive, the sard regulator sat for a couple months then I bought it.

FastNFurious

haha, you don't bleed fuel lines do you?? I would think any air in the line would just get shot out of the injectors into the combustion chamber.

Sprockets

iTrader: (6)

I don't smell gas. The car starts right up and runs fine. It's probably the check valve (or lack of one) in the Walbro. Maybe there's nothing to worry about, but it was just an observation. I guess I'll find out for sure when I install my Hondata and get it tuned.