My fuel pressure wont move
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My fuel pressure wont move
I Just installed 1600cc secondaries with a new fuel rail. I am trying to adjust the FPR but it is stuck at 45 psi. How the hell do i adjust it.
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Thats why im asking this question because i have done that numerous times with no result. The needle still wont move. Could it be that it is not grounded to the car? If so, then how do I go about grounded it? Do i just take a wire and attach one end to the car and one end to the FPR. Thanks
-Floman
-Floman
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You don't ground the regulator to the car. All you do is adjust the allen screw on top of the regulator. Screwing it in will give you more pressure and screwing it out will drop the pressure. Also you are saying that you have 45psi of fuel pressure. Is that at idle? Or is it with the car off and the fuel relay jumpered?
To properly adjust it start the car and let it idle. Pull off the vacuum line off of the regulator and then adjust the "base pressure" to anywhere between 30-34 psi by screwing in or out the hex screw. Now reattach the vacuum line back on the nipple on the fuel regulator and your done. Your pressure at idle should now be around 38-40 psi. Try that first.
R.K.
To properly adjust it start the car and let it idle. Pull off the vacuum line off of the regulator and then adjust the "base pressure" to anywhere between 30-34 psi by screwing in or out the hex screw. Now reattach the vacuum line back on the nipple on the fuel regulator and your done. Your pressure at idle should now be around 38-40 psi. Try that first.
R.K.
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Does it go down at all? If it never moves from 45 the gauge is broken, if it won't go up, your fuel pump may be at its pressure limit. If your gauge is electrical then grounding would be an issue, but if its just a regular gauge that mounts right on the FPR there's no electrical stuff to consider.
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It is just a regular gauge that mounts on the FPR. Also it is at idle when the fuel pressure reads 45psi. It goes up when i rev it but even when I take the vacum hose off and adjust the screw the pressure will not move. Can someone clear up for me how the FPR is supposed to be hook up. Maybe the problem is in the installation
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Originally Posted by floman
It is just a regular gauge that mounts on the FPR. Also it is at idle when the fuel pressure reads 45psi. It goes up when i rev it but even when I take the vacum hose off and adjust the screw the pressure will not move. Can someone clear up for me how the FPR is supposed to be hook up. Maybe the problem is in the installation
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Originally Posted by crazyrx7
To properly adjust it start the car and let it idle. Pull off the vacuum line off of the regulator and then adjust the "base pressure" to anywhere between 30-34 psi by screwing in or out the hex screw. Now reattach the vacuum line back on the nipple on the fuel regulator and your done. Your pressure at idle should now be around 38-40 psi. Try that first.
R.K.
R.K.
If your car is idling, and you set the base fuel pressure at atmospheric (ie, with the vac line off) to X psi, once you hook the vacuum line back up, your fuel pressure will drop, not increase, since the regulator is now seeing vaccum.
So, just as an example: Base fuel pressure of 40psi at atmospheric, would be around 37 psi at idle.
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Originally Posted by eViLRotor
This is not correct.
If your car is idling, and you set the base fuel pressure at atmospheric (ie, with the vac line off) to X psi, once you hook the vacuum line back up, your fuel pressure will drop, not increase, since the regulator is now seeing vaccum.
So, just as an example: Base fuel pressure of 40psi at atmospheric, would be around 37 psi at idle.
If your car is idling, and you set the base fuel pressure at atmospheric (ie, with the vac line off) to X psi, once you hook the vacuum line back up, your fuel pressure will drop, not increase, since the regulator is now seeing vaccum.
So, just as an example: Base fuel pressure of 40psi at atmospheric, would be around 37 psi at idle.
**** I got all screwed up with the numbers. What I meant to type was with the vacuum line back on you should get between 28 and 32 psi of fuel pressure. Sorry my mistake.
R.K.
#13
Quick check of FPR plumbing:
1. There should be a line coming from the secondary fuel rail to the side of the FPR
2. The other side port on the FPR should be plugged.
3. The bottom port on the FPR should connect to the return line that goes back to the tank.
-Max
1. There should be a line coming from the secondary fuel rail to the side of the FPR
2. The other side port on the FPR should be plugged.
3. The bottom port on the FPR should connect to the return line that goes back to the tank.
-Max
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Ok so i have it hooked up right thankfully. It doesnt matter if the vacum line is on or off the fuel pressure is stuck at 40 or 45. Its weird. When i rev it up sometimes it spikes to like 100 but lately it has been moving only about 10 psi up. I do just have the FPR just sittling there not mounted to anything. Could that be the problem? Its boggling my mind. I have to get the car running, my family is fighting over one car and its is driving everyone insane. Thanks
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Looks like you have it hooked up right. Do you have anyone that you can swap the fpr with?
Thats what I did when I wasn't getting enough pressure and found out my fuel pump "o" ring was cracked and leaking fuel.
R.K.
Thats what I did when I wasn't getting enough pressure and found out my fuel pump "o" ring was cracked and leaking fuel.
R.K.
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Make sure you mount that thing to something, if the gauge isn't bad already it won't last long getting knocked around in the engine bay. Sounds like you've got a bad gauge or a bad pump.
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What does your pressure guage say when the car is off? If it still says 45psi then your guage is hooped. If it drops to zero then its alright. Also what fuel pump are you running? Is it stock or aftermarket?
R.K.
R.K.
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if u gauge is accutate, you probably have a kink in ur return line or too much pump. if u free rev it and get 100psi id you probably have the wrong type of fpr
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Thanks for the help guys. I have also notice that fuel leaks out of the vacum nipple on the FPR. Also I have a walbro 255 fuel pump. The gauge goes down to zero when the car is off.
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Fuel isn't supposed to be coming out that nipple. It sounds like you ruptured the diaphram in the regulator. Its time for a new one. Get the aeromotive one.
R.K.
R.K.
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Ok so i got a new fuel pressure regulator and put it on my car. The old one was definetly bad. I know no this because i can change the fuel pressure with that screw at the top and before I could not. But, the car runs the same, like ****. I dont know what the hell is happening but i do notice something weird. When i turn on the car, there is a hissing sound that wasnt there before i put the fuel stuff on. I checked all the vacum hoses and they are intacted. Is there anyone who can tell me what that noise is or why my car is not running properly. Please help me. Ahhhhhhh this is driving me mad. PS if you live in Austin, I would very much apriciate it if you would come out to my house and look at my car and see if you can help out.
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Try changing your plugs. They are probably fouled due to you running so rich. The hissing sound you have to start investigating on your own. Just make sure all of your fuel connections are tight. Also do you have a boost gauge? What vacuum are you pulling at idle? You might have forgot to cap a vacuum line or something like that and now you have a leak. At least you figured out the fpr proble.
R.K.
R.K.