Is there suppose to be pressure in the line acouple hours after shutting it off ?
fuel pressure
- Thread starter speer
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Depends on the car. Go and buy a book on your car, if you really want to know the details.
I know in my Taurus there are multiple sensors. Even if you have the car turned off and you pull the fuel filter, and the fuel line loses pressure, the fuel pump will kick on and drain your tank on you.
The idea is to remove any bubbles before the car starts so that your fuel injectors are ready to go.
You either have to pull the circuit or disconnect the battery to avoid this. No power = no pumps or sensors.
I know in my Taurus there are multiple sensors. Even if you have the car turned off and you pull the fuel filter, and the fuel line loses pressure, the fuel pump will kick on and drain your tank on you.
The idea is to remove any bubbles before the car starts so that your fuel injectors are ready to go.
You either have to pull the circuit or disconnect the battery to avoid this. No power = no pumps or sensors.
Ya did a few filters and got sprayed. Thats what I thought Going to replace regulator and see what happens Got a book but cant find the thing bet I will after I done Thanks
Remove the fuel pump relay when you do fuel filters. Or remove the gas cap, its how I have always done it on fuel injected cars.
Originally Posted By: speer
Is there suppose to be pressure in the line acouple hours after shutting it off ?
On most cars of the MPEFI era, yes. The pressure in the fuel lines and rails can persist for many hours after shutdown. SOP when I change an inline filter on one of my EFI cars is to pull the fuel pump relay and then idle the engine until it stalls.
If there's a pressure test port on the fuel rail, you can connect a gauge there and some of them have a pressure bleed button. Just throw the bleed hose in a container and bleed fuel into it until it stops flowing.
Is there suppose to be pressure in the line acouple hours after shutting it off ?
On most cars of the MPEFI era, yes. The pressure in the fuel lines and rails can persist for many hours after shutdown. SOP when I change an inline filter on one of my EFI cars is to pull the fuel pump relay and then idle the engine until it stalls.
If there's a pressure test port on the fuel rail, you can connect a gauge there and some of them have a pressure bleed button. Just throw the bleed hose in a container and bleed fuel into it until it stops flowing.
Originally Posted By: mechanicx
That a good thing. The longer the fuel pressure hold pressure the better. You wouldn't want to change the fuel pressure regulator. The residual pressure is a sign that it is working along with your anti-drainback valve.
Changed it wish I would have read your post before I did,$60 but did plugs wires cap and rotor along with filters too. Guess I'll see what it does in the morning. Thanks
That a good thing. The longer the fuel pressure hold pressure the better. You wouldn't want to change the fuel pressure regulator. The residual pressure is a sign that it is working along with your anti-drainback valve.
Changed it wish I would have read your post before I did,$60 but did plugs wires cap and rotor along with filters too. Guess I'll see what it does in the morning. Thanks
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I have heard the FPR can get small leaks in their diaphragm and still function correctly/within spec which allows a little gas into your vacuum lines.
I think mine is doing this as the metal hose nipple on my FPR has white corrosion looking stuff on it. While every other vacuum line/nipple are clean. Noticed that when I put in a new EGR valve. It's working still and I didn't have the money for a new one.
I think mine is doing this as the metal hose nipple on my FPR has white corrosion looking stuff on it. While every other vacuum line/nipple are clean. Noticed that when I put in a new EGR valve. It's working still and I didn't have the money for a new one.
Originally Posted By: Texan4Life
I have heard the FPR can get small leaks in their diaphragm and still function correctly/within spec which allows a little gas into your vacuum lines.
I think mine is doing this as the metal hose nipple on my FPR has white corrosion looking stuff on it. While every other vacuum line/nipple are clean. Noticed that when I put in a new EGR valve. It's working still and I didn't have the money for a new one.
I read today to put a clear piece of hose in between the reg and vac line and you can see if its leaking thru the clear hose
I have heard the FPR can get small leaks in their diaphragm and still function correctly/within spec which allows a little gas into your vacuum lines.
I think mine is doing this as the metal hose nipple on my FPR has white corrosion looking stuff on it. While every other vacuum line/nipple are clean. Noticed that when I put in a new EGR valve. It's working still and I didn't have the money for a new one.
I read today to put a clear piece of hose in between the reg and vac line and you can see if its leaking thru the clear hose
Originally Posted By: speer
Originally Posted By: mechanicx
That a good thing. The longer the fuel pressure hold pressure the better. You wouldn't want to change the fuel pressure regulator. The residual pressure is a sign that it is working along with your anti-drainback valve.
Changed it wish I would have read your post before I did,$60 but did plugs wires cap and rotor along with filters too. Guess I'll see what it does in the morning. Thanks
It had to be the reg starts good now thaks for help
Originally Posted By: mechanicx
That a good thing. The longer the fuel pressure hold pressure the better. You wouldn't want to change the fuel pressure regulator. The residual pressure is a sign that it is working along with your anti-drainback valve.
Changed it wish I would have read your post before I did,$60 but did plugs wires cap and rotor along with filters too. Guess I'll see what it does in the morning. Thanks
It had to be the reg starts good now thaks for help
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