Will a dirty filter cause fuel pressure to drop? (pictures inside)
10-25-2006, 01:54 AM
#1
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Will a dirty filter cause fuel pressure to drop? (pictures inside) The last 3 pictures are of my mesh filter before my fuel pump (eliminator).
The first one is of my paper filter after the fuel pump.
Will me changing the paper filter fix my fuel pressure dropping issues?
Does the filter look dirty? Its only been on for about 2k miles.
Also, what is that darker part on my mesh screen filter?
TIA.
The first one is of my paper filter after the fuel pump.
Will me changing the paper filter fix my fuel pressure dropping issues?
Does the filter look dirty? Its only been on for about 2k miles.
Also, what is that darker part on my mesh screen filter?
TIA.
10-25-2006, 07:56 AM
#2
Suggest... you cut the paper filter open, and look down in the pleats. That's where you most likely will see the crud.[if the is any.]
The dark area on the SS screen is likely the area where the mesh is welded.
From what I can see, the filters are not the issue. You have something else going on.
Is that paper filter flow rated to operate in a EFI system?
Other items of "interest".
1. Low voltage.
2. Pump on it's way south.
3. Leaky intake line, allowing the pump to cavitate.
4. Insufficient venting on the tank.
5. Kinked lines.
HTH,
Back to
The dark area on the SS screen is likely the area where the mesh is welded.
From what I can see, the filters are not the issue. You have something else going on.
Is that paper filter flow rated to operate in a EFI system?
Other items of "interest".
1. Low voltage.
2. Pump on it's way south.
3. Leaky intake line, allowing the pump to cavitate.
4. Insufficient venting on the tank.
5. Kinked lines.
HTH,
Back to
10-25-2006, 12:13 PM
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Originally Posted by Old Geezer
you cut the paper filter open, and look down in the pleats. That's where you most likely will see the crud.[if the is any.]
The dark area on the SS screen is likely the area where the mesh is welded.
From what I can see, the filters are not the issue. You have something else going on.
Is that paper filter flow rated to operate in a EFI system?
Other items of "interest".
1. Low voltage.
2. Pump on it's way south.
3. Leaky intake line, allowing the pump to cavitate.
4. Insufficient venting on the tank.
5. Kinked lines.
HTH,
Back to
The dark area on the SS screen is likely the area where the mesh is welded.
From what I can see, the filters are not the issue. You have something else going on.
Is that paper filter flow rated to operate in a EFI system?
Other items of "interest".
1. Low voltage.
2. Pump on it's way south.
3. Leaky intake line, allowing the pump to cavitate.
4. Insufficient venting on the tank.
5. Kinked lines.
HTH,
Back to
This is the scenario. When I first got the car back (january of this year) fuel pressure was steady all the time, never fluctuated at all and was steady at 61 or so PSI all the time.
Keep in mind, Allan Futral built the whole setup, so I would assume the filter should be sufficient.
I had constant over heating issues so I sent the car back to futral to fix sometimes around may. I got the car back probably june or so, and then i noticed that the fuel pressure started dipping down and fluctuating.
soon after that, the fuel pump took a **** on me and dropped down to like 30-40psi, so i shut the car off and had it towed home.
I sent the fuel pump back to aeromotive, they said cavitation was causing the issue, and that i may need to change the AN fittings to 10 instead of the 12 its on right now.
They rebuilt the unit and sent it back to me. I re-installed it, 3 days later I blew the **** out of my clutch, lol.
So, i finally started driving the car again 2 weeks ago and it is worrying me that the fuel pump keeps doing this. I called aeromotive, and they said to try changing the filter since it hasnt been changed and there apparently was debre(SP?) somewhere (cant remember if it was from the pump or where.
I do have a system connected to my car, and noticed when I hit it HARD the fuel pressure drops like 5-10 psi, so i made sure not to do it again after noticing it.
Another question, are you supposed to teflon the fittings when putting the setup back together, or just slap it on how it is?
When I re-connected the fuel lines, I started the car and made sure it was ok, and didnt see anything leaking.
I dont think it would be kinked lines, cause everything seems to be tucked up under the undercarriage pretty nicely.
How would I check If the tank is venting sufficiently?
Keep in mind, ive only got about 2500 miles on the fuel pump.
Thanks again for any help you can provide.
10-25-2006, 01:20 PM
#4
alot of people have had problems with areomotive fuel pumps, I wont ever try one because of that.
it is possible that a dirty filter would prevent fuel flow which could drop fuel pressure, but i dont think thats likley in your case. I think its the pump.
if the fuel fittings are -AN type then you dont need any teflon tape, if they are NPT fittings then yes you need teflon tape.
it is possible that a dirty filter would prevent fuel flow which could drop fuel pressure, but i dont think thats likley in your case. I think its the pump.
if the fuel fittings are -AN type then you dont need any teflon tape, if they are NPT fittings then yes you need teflon tape.
10-25-2006, 04:20 PM
#6
Hmmmmmmm...this is a good question. On mine, I see a regular fuel pressure drop of 5 psi at WOT, and something less than that just giving it moderate throttle - stock fuel system, bolt-on LS1. I'm gonna replace my fuel filter (even though it is only about 15k miles old), and see if that makes a difference. I'm beginning to wonder if a slight pressure drop is acceptable, or if it is a dirty filter.
Not apples to apples, but at least another data point for you.
Not apples to apples, but at least another data point for you.
10-25-2006, 06:40 PM
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Originally Posted by MeentSS02
Hmmmmmmm...this is a good question. On mine, I see a regular fuel pressure drop of 5 psi at WOT, and something less than that just giving it moderate throttle - stock fuel system, bolt-on LS1. I'm gonna replace my fuel filter (even though it is only about 15k miles old), and see if that makes a difference. I'm beginning to wonder if a slight pressure drop is acceptable, or if it is a dirty filter.
Not apples to apples, but at least another data point for you.
Not apples to apples, but at least another data point for you.
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10-25-2006, 06:44 PM
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Originally Posted by MeentSS02
Hmmmmmmm...this is a good question. On mine, I see a regular fuel pressure drop of 5 psi at WOT, and something less than that just giving it moderate throttle - stock fuel system, bolt-on LS1. I'm gonna replace my fuel filter (even though it is only about 15k miles old), and see if that makes a difference. I'm beginning to wonder if a slight pressure drop is acceptable, or if it is a dirty filter.
Not apples to apples, but at least another data point for you.
Not apples to apples, but at least another data point for you.
Also, do you think running injector cleaner through it could help? I wouldnt think anything would be able to get clogged in the fuel lines since gas is kind of corrosive.
10-25-2006, 07:18 PM
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How are you feeding the pump? A factory intank pump can't keep up with an Eliminator. If you can't feed the pump fast enough it will indeed cavitate and fuel pressure will drop.
You mention a system. You mean audio system? If so and you drop 5-10 psi from your regulated pressure then your pump is not getting good voltage at any time, let alone when your amp is sucking away. Check the wiring to the pump relay and the ground. The Eliminator should have a 10 guage wire on both terminals. It will easily want 20 amps under load.
The Eliminator uses A/N fittings which are straight thread and use no sealer, only an o-ring.
Your filters are fine. A dirty 10 micron post pump filter will usually take on a gray color. There is no obvious debis in the 100 micron pre-filter. Make sure you don't put them in backwards.
You mention a system. You mean audio system? If so and you drop 5-10 psi from your regulated pressure then your pump is not getting good voltage at any time, let alone when your amp is sucking away. Check the wiring to the pump relay and the ground. The Eliminator should have a 10 guage wire on both terminals. It will easily want 20 amps under load.
The Eliminator uses A/N fittings which are straight thread and use no sealer, only an o-ring.
Your filters are fine. A dirty 10 micron post pump filter will usually take on a gray color. There is no obvious debis in the 100 micron pre-filter. Make sure you don't put them in backwards.
10-25-2006, 07:48 PM
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Originally Posted by andereck
How are you feeding the pump? A factory intank pump can't keep up with an Eliminator. If you can't feed the pump fast enough it will indeed cavitate and fuel pressure will drop.
You mention a system. You mean audio system? If so and you drop 5-10 psi from your regulated pressure then your pump is not getting good voltage at any time, let alone when your amp is sucking away. Check the wiring to the pump relay and the ground. The Eliminator should have a 10 guage wire on both terminals. It will easily want 20 amps under load.
The Eliminator uses A/N fittings which are straight thread and use no sealer, only an o-ring.
Your filters are fine. A dirty 10 micron post pump filter will usually take on a gray color. There is no obvious debis in the 100 micron pre-filter. Make sure you don't put them in backwards.
You mention a system. You mean audio system? If so and you drop 5-10 psi from your regulated pressure then your pump is not getting good voltage at any time, let alone when your amp is sucking away. Check the wiring to the pump relay and the ground. The Eliminator should have a 10 guage wire on both terminals. It will easily want 20 amps under load.
The Eliminator uses A/N fittings which are straight thread and use no sealer, only an o-ring.
Your filters are fine. A dirty 10 micron post pump filter will usually take on a gray color. There is no obvious debis in the 100 micron pre-filter. Make sure you don't put them in backwards.
As far as audio system, yes, I have a 1500 watt amp that powers 2 subs. Where would the pump relay be? is it just the power and ground that is attached to the pump?
Whats wierd though, is when I first got the car, I wasnt having any issues at all, steady fuel pressure at idle or WOT, but soon as I got it back after sending it out I started noticing these issues.
Do you think my alternator needs to be replaced, or could it just possibly be part of the wiring got grounded out or something?
I havent changed the wiring at all for it, so I dont know how it could be that, unless it was too small to begin with and it just took a toll on the pump (and also after it was rebuilt, it wasnt a new unit they sent me).
10-25-2006, 07:59 PM
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You should trace the wires leaving the pump to see where they go. The ground wire needs to be attached to a clean metal part of the body with a solid connection. Check the ring terminals for a tight crimp/solder connection. If there is a loose connection it will fail when the amp draw gets high enough, or fail intermittantly.
There is no excuse for not having a relay, nor is there an option.
You must power the relay/pump with a heavy gauge wire with the feed coming from the battery. I personally prefer not to hook directly to the alternator post, though some do.
Your alternator could be taxed, Powermaster offers high amp upgrades that will fit your application.
Get a large cap for your amp and it will leave more power for the rest of the car.
Keep in mind that fuel pressure that rolls backwards is a sign of low volume and it can damage your engine very easily.
There is no excuse for not having a relay, nor is there an option.
You must power the relay/pump with a heavy gauge wire with the feed coming from the battery. I personally prefer not to hook directly to the alternator post, though some do.
Your alternator could be taxed, Powermaster offers high amp upgrades that will fit your application.
Get a large cap for your amp and it will leave more power for the rest of the car.
Keep in mind that fuel pressure that rolls backwards is a sign of low volume and it can damage your engine very easily.
10-25-2006, 08:02 PM
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ya, ive already got a cap on there. I know about the issue with the low fuel pressure, thats why i wanna take care of it before it takes care of me, lol.
10-26-2006, 12:13 AM
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Originally Posted by MeentSS02
Hmmmmmmm...this is a good question. On mine, I see a regular fuel pressure drop of 5 psi at WOT, and something less than that just giving it moderate throttle - stock fuel system, bolt-on LS1. I'm gonna replace my fuel filter (even though it is only about 15k miles old), and see if that makes a difference. I'm beginning to wonder if a slight pressure drop is acceptable, or if it is a dirty filter.
Not apples to apples, but at least another data point for you.
Not apples to apples, but at least another data point for you.
10-26-2006, 07:11 AM
#14
Originally Posted by 2000 Tran Zam
So your running stock fuel pump, not a 255 walbro or anything else then correct?
Also, do you think running injector cleaner through it could help? I wouldnt think anything would be able to get clogged in the fuel lines since gas is kind of corrosive.
Also, do you think running injector cleaner through it could help? I wouldnt think anything would be able to get clogged in the fuel lines since gas is kind of corrosive.
10-26-2006, 07:13 AM
#15
Originally Posted by 00TurboT/A
Thats normal under WOT. Your good still
10-26-2006, 11:58 AM
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Originally Posted by andereck
You should trace the wires leaving the pump to see where they go. The ground wire needs to be attached to a clean metal part of the body with a solid connection. Check the ring terminals for a tight crimp/solder connection. If there is a loose connection it will fail when the amp draw gets high enough, or fail intermittantly.
There is no excuse for not having a relay, nor is there an option.
You must power the relay/pump with a heavy gauge wire with the feed coming from the battery. I personally prefer not to hook directly to the alternator post, though some do.
Your alternator could be taxed, Powermaster offers high amp upgrades that will fit your application.
Get a large cap for your amp and it will leave more power for the rest of the car.
Keep in mind that fuel pressure that rolls backwards is a sign of low volume and it can damage your engine very easily.
There is no excuse for not having a relay, nor is there an option.
You must power the relay/pump with a heavy gauge wire with the feed coming from the battery. I personally prefer not to hook directly to the alternator post, though some do.
Your alternator could be taxed, Powermaster offers high amp upgrades that will fit your application.
Get a large cap for your amp and it will leave more power for the rest of the car.
Keep in mind that fuel pressure that rolls backwards is a sign of low volume and it can damage your engine very easily.
10-26-2006, 12:47 PM
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I would think the only thing possible would be either faulty alternator, or maybe some of the wiring came loose at the terminals or maybe wasnt tightned all the way down onto the pump.
Ill check tonight when i replace my filter.
Ill check tonight when i replace my filter.
10-26-2006, 04:36 PM
#19
System Info Just to let everybody know what Alan has since he cant explain it.
Sumped '98 tank at rear of tank with baffles. -10 AN from the tank to the fuel pump and filters,then 1\2" hard line to fuel rail y-block. Stock line as a return. All AN fittings w\o-ring sealing on component side. Proper EFI filters..the stainelss 100m before and paper 10m after.
Aeromotive billet controller with 10ga wires staright to battery which are both in the rear of the car. Also 10ga wiring to the pump\ground.
Sumped '98 tank at rear of tank with baffles. -10 AN from the tank to the fuel pump and filters,then 1\2" hard line to fuel rail y-block. Stock line as a return. All AN fittings w\o-ring sealing on component side. Proper EFI filters..the stainelss 100m before and paper 10m after.
Aeromotive billet controller with 10ga wires staright to battery which are both in the rear of the car. Also 10ga wiring to the pump\ground.
Last edited by Futral Motorsports; 10-26-2006 at 05:02 PM.
10-26-2006, 05:36 PM
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Originally Posted by jstacy
Filters are backwards if the 10M is on the inlet side.