Fuel pump periodically running while car is off?
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From: Gary, In
Fuel pump periodically running while car is off? I'v asked this before but still can't figure it out and have a new twist to my problem now. I'm installing a regulator to try and get my pressure under control so I pulled both the factory fuse and hotwire kit fuse to release the pressure and noticed the pressure jumped up again after pulling both fuses? I know it was wired according to the instructions. I just can't figure this out?
It's a Racetronix 340 pump with a hotwire kit.
It's a Racetronix 340 pump with a hotwire kit.
I have a fuel pressure gauge on my fuel rail and noticed the pressure will slowly leak down on the system after shut down. But I've came back out to the car hours later and noticed that my fuel pressure is back up to 60 signaling to me that the pump must have kicked on and pressurized the fuel system again. Is your power wire wired to the alternator or the power supply lead up at the fuse panel?
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From: Gary, In
I have a fuel pressure gauge on my fuel rail and noticed the pressure will slowly leak down on the system after shut down. But I've came back out to the car hours later and noticed that my fuel pressure is back up to 60 signaling to me that the pump must have kicked on and pressurized the fuel system again. Is your power wire wired to the alternator or the power supply lead up at the fuse panel?
I don't know if it's hurting it or not but I'm thinking about wiring it to the back of the alternator to see if it quits doing it. The pump cycles at the turn of the key but I haven't taken the time to sit there and wait to hear it cycle with the key off.
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From: Gary, In
Well, that's not the problem. My problem got a lot stranger now.....I've pulled the wiring connectors off the pump and guess what? My pressure jumped up after they were disconnected! There's no physical way this should happen! Is my car haunted? lol
Is the tank vented? That's the only way it can actually build pressure on it's own either that or it's somehow heating up the fuel (Thermal expansion) in the line where the gauge is and it has no place to bleed off the pressure.
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From: Gary, In
lol, that's what I'm figuring over haunted. Well, I know nothing is misconnected so clogged would be the next step. All the time I thought it was a wiring issue till now. Are these vented tanks? I always figured that was the point of the whole evap bs....to keep fumes inside the tank? I'm in the process of installing a c5 regulator setup now and will be pulling the pump assembly. What should I be looking for/check?
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From: Central Cal.
ALL tanks are vented in some way- in the bad ol' days, to the atmosphere, more lately thru vapor recovery systems that let the vapors be ingested by the engine.
Disconnect the vapor tube going from tank to the Evap valve and see if it's clear.
Disconnect the vapor tube going from tank to the Evap valve and see if it's clear.
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From: Gary, In
Well, the original regulator was bad. Even though it doesn't have vacuum going to it I was able to suck air through the nipple. So that was hopefully my high pressure problem and hopefully the c5 reg will take care of that.
Are you relieving the fuel system after the pump is disconnected? Disconnect the pump then crank the engine until all fuel is out of the system? If not, is it possible under hood heat is causing the stagnant fuel to re-pressurize the system?
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From: Gary, In
Car's been sitting in the garage all winter. It does it cold or hot. I just got it back together and will see what happens.