How long should fuel pressure be maintained after shutdown?
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From: Mississauga, Ontario Canada
Car: 1987 GTA
Engine: 5.7
Transmission: T5WC
Axle/Gears: 3:27
How long should fuel pressure be maintained after shutdown?
Right in the title. Just want to know how long after I shut off the should the fuel pressure stay up. Is it supposed to be indefinite or does it blled down after a 1/2 hour or so?
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From: Readsboro, VT
Car: 85 IROC-Z / 88 GTA
Engine: 403 LSx (Pending) / 355 Tuned Port
Transmission: T56 Magnum (Pending) / T5
Axle/Gears: 3.42 / ?
well, it depends. If the drainback valve in the fuel pump is functional, and you don't have any sort of leaks, it should last quite a while. Could take up to a couple hours for the pressure to bleed off completely.
But, if you're lucky like me, your fuel pump drainback valve doesn't work, and the pressure bleeds off immediately. I'm on my 2nd fuel pump and it's doing it now too.
But, if you're lucky like me, your fuel pump drainback valve doesn't work, and the pressure bleeds off immediately. I'm on my 2nd fuel pump and it's doing it now too.
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Joined: Jan 2000
Posts: 1,180
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From: Mississauga, Ontario Canada
Car: 1987 GTA
Engine: 5.7
Transmission: T5WC
Axle/Gears: 3:27
I went from stock to Holley and had nothing but problems with it. So I went back to a carter last year. My pressure holds 40 some pounds for about an hour then slowly bleeds off. Is that a problem?
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From: Lower Salford, PA
Car: 1987 Camaro Z-28
Engine: 6.3L Victor EFI
Transmission: Tremec TKO 600
Axle/Gears: Moser 9"/4.11 Trac-Lok
The Holley 255 lph pump has no valve. Mine loses pressure in 5 seconds. No problems other than slightly extended crank times on startup.
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From: Cincinnati,Ohio
Car: 1991 BandittII Firebird
Engine: 5.7 HSR
Transmission: 700R4
Axle/Gears: 3.27 9 bolt
Originally posted by Ricktpi
The Holley 255 lph pump has no valve. Mine loses pressure in 5 seconds. No problems other than slightly extended crank times on startup.
The Holley 255 lph pump has no valve. Mine loses pressure in 5 seconds. No problems other than slightly extended crank times on startup.
)and it'll hold pressure for a few seconds but i don't have any extended crank time
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