fuel pressure queston
07-05-2007, 11:02 PM
#1
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fuel pressure queston
i recently put on a fpr and when i try to adjust the pressure with vac off the pressure goes up to 40 and drops to around 30 to 35 and when i put the vac line on it stays the same and i also can't get the pressure above 40psi. do you think the regulator could be bad or the gauge bad.
07-05-2007, 11:06 PM
#2
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RE: fuel pressure queston
The pressure will drop when the vacuum is hooked back up, that's normal. If you can't get past 40 with your vac unhooked something's wrong. ~43psi unhooked is a good number to shoot for, should be around 38 when reconnected. Are you saying that 40psi unhooked will drop it down to 30 when hooked back up? That's a pretty big drop
07-05-2007, 11:07 PM
#3
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RE: fuel pressure queston
ORIGINAL: LTnone
The pressure will drop when the vacuum is hooked back up, that's normal. If you can't get past 40 with your vac unhooked something's wrong. ~43psi unhooked is a good number to shoot for, should be around 38 when reconnected
The pressure will drop when the vacuum is hooked back up, that's normal. If you can't get past 40 with your vac unhooked something's wrong. ~43psi unhooked is a good number to shoot for, should be around 38 when reconnected
07-05-2007, 11:57 PM
#4
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RE: fuel pressure queston
when i hook the vac up the gauge shows pressure of around 30 psi and with it unhooked i increase the pressure and it goes to 40psi and immediatly drops to around 35 and i keep increasing and it does nothing and when i decrease the fuel pressure it will jump to 40 and again back down to 35 and i keep decreasing and nothing, so now i have no idea where my fuel pressure is because of this and i'm affraid to drive it because it mite be too lean, what does this sound like to you guys.
07-06-2007, 12:33 AM
#6
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Location: Katy, Texas
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RE: fuel pressure queston
ORIGINAL: LTnone
The pressure will drop when the vacuum is hooked back up, that's normal. If you can't get past 40 with your vac unhooked something's wrong. ~43psi unhooked is a good number to shoot for, should be around 38 when reconnected. Are you saying that 40psi unhooked will drop it down to 30 when hooked back up? That's a pretty big drop
The pressure will drop when the vacuum is hooked back up, that's normal. If you can't get past 40 with your vac unhooked something's wrong. ~43psi unhooked is a good number to shoot for, should be around 38 when reconnected. Are you saying that 40psi unhooked will drop it down to 30 when hooked back up? That's a pretty big drop
07-06-2007, 02:25 AM
#7
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RE: fuel pressure queston
i tried it again and the pressure was on 35 with vac on and took the vac off adjusted it and it went to 40psi and i adjusted it alittle more and the pressure fell to 34psi and i turn the fpr back and forth and the pressure would not move but maybe 1 or 2 psi and the last check i did the gauge showed 28psi with vac on and also when i turn the car off should pressure stay on the gauge or will the gauge go back down to 0, i'm really confused if this is a regulator problem or gauge problem.
07-06-2007, 04:12 AM
#9
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Location: Haverhill, MA
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RE: fuel pressure queston
i left my car unstarted for about 36 hours recently and checked it this morning while it was cold. definitely above 30 psi with vaccum on and when i adjusted it earlier this week it was at about 39 psi vaccum disconnected.
signs of a bad fuel pump or computer just doing its thing?
gauge is liquid filled summit. BBK regulator.
signs of a bad fuel pump or computer just doing its thing?
gauge is liquid filled summit. BBK regulator.