I have two logs and I am curious to know if these are indicative of a failing fuel pump. That is my diagnosis and before I go change the pump I wanted a co-sign!
Fuel Pressure drops considerably during a WOT run. I've got one log where I was able to maintain a proper fuel pressure ratio but I see the FP dropping off and then one where the A/F ratio was catostrphically dangerous.
The files are arranged in date order 2/26 and then 2/28
I wouldnt doubt that pump is going bad,and or the filter is clogged.
Are you running a paper filter before the pump?
How is the pump wired?
How is the fuel being picked up by the pump?
fuel cell,stock sumped tank?
you are definetly losing fuel pressure so if these things are right i would be sending back to rebuild or just scrap that aeromotive pump and go a different route.
I am running a steel 100 micron by aeromotive pre filter and then a 24 micron post filter.
The pump is wired through a caspet HD fuel pump relay with a signal from the original fuel pump power source. Power to the relay is from the alternator and ground to the battery.
The pick up is not a recommended method, but has posed no problems thus far. It is based on the stock system.
but with -10 feeding the pump and -8 feeding the rail.
I am starting with the least expensive fixes first. I think it might be the relay.
If it were a clogged filter I feel I would never be able to get the Air fuel ratios into the 11's under load. So something in my opinion is happening electronically.
Relay anyone.
I am curious why so many dislike the aeromotive pumps.
I like my Aeromotive A1000, and the only time I have any problems is when I am at or below 1/2 tank. I have another tank with a back sump that may help. The car would nose over hard in second and third. I am feeding the pump with -12 line, and -8 to the engine.
In my exp they never lasted long on a car that was driven alot.
I always powered them correctly but eventually they would start running
slower and slower and not keeping up.
Its not really obvious until you hear how well a new one sounds next to your old one.
I am wondering if my issue could be my pick up method. Is it coming uncovered.
I am not using the recommended sump. INstead I am using a pick up similar to a stock pick up. I've been messing with this set up for over 7 months off and on and I have never had a problem until now. Boost has been relatively low before 10 lbs. Now I am working my way toward my max range on pump gas. 15 - 18 psi.
The difference before is I wasn't doing extended highway pulls. I would do a quick WOT going from a dead stop up to 3rd gear. This usually happened pretty quickly. Now I may be having an issue with the fuel level and the type of acceleration over an extended period of time.
I thought I had 1/2 tank of fuel when I made the pulls logged in the attachment.
Has anyone any experience with the pick up coming uncovered and what happens with fuel pressure.
using .63 bsfc at 350 LBS/ HR it should support over 550 horse.
I have some friends that have used the A1000 pump about 7 years ago. They had issues with their pumps lasting. I understand Aeromotive has made some changes to thier pump design and the durabilty of the pump has been greatly improved.
But we'll see, if indeed I have a pump issue although I doubt it.
Do you guys recommend Magnafuel.
I attached the real chart for the A1000.
Either way the a1000 should be able to handle 15 lbs of boost.
I figure if the the pickup comes uncovered and picks fuel back up. You would see sporadic fuel pressure reading, meaning a fluctuation up and down. Not just a steady drop.
Are you using their fuel controller? It is recommended for street use.
and most likely the only way to make them live a long street life.
They do offer a cheap rebuild on thier pumps though.
Are you using their fuel controller? It is recommended for street use.
and most likely the only way to make them live a long street life.
They do offer a cheap rebuild on thier pumps though.
I picked one of these up today and will wire it in this evening.
This will eliminate the need for a relay, which is where I feel my issue is. Nothing else adds up;
* Clogged fuel filters(pre & after) can't be due to air fuel ratios achieved at the onset of the WOT pull.
* Uncovered pickup - I theorize if my pickup was coming uncovered, the fuel pressure would be eractic. Jumping from one PSI to another based on the pickups ability to stay covered.
* Failed or failing pump - I theorize this can't be the issue. I switched out the pump for another aeromotive pump with less than 1 hour run time. Used to run this same engine on an engine dyno.
One area I have not looked into is the fuel pressure regulator. Again I am trusting Aeromotive - never had an issue here, but this is a part of the fuel system. This regulator only came into use with this current build - and was brand new. So only 6 months use. how to test the regulator
You can simulate boost if you have a small air regulator. The a1000 should make over 100psi fp no problem.
Now don't forget, pressure and volume are two different thing so you have more testing to do.
I have a a1000 running over a year now with no controller. I run 25 psi boost with alky. I have 83lb injectors. Duty cycle around 70% at wot. I did just get a controller myself. That should add life to the pump.
Came home and put a vacum check on the regulator, only to find the thing isn't holding vacum. I would have to say this is probably a large contributor to my issue.
I want to replace the diaphram and see if things get better with the regulator and then the next change will be the fuel controller.
"This will eliminate the need for a relay, which is where I feel my issue is."
If the relay is turning on/off as it is designed to do, the next step is to see what the VDC into and out are.. I'd consider the relay being bad as like being pregnant... Either are or are not.
As for the regulator.. U sure the vac source is not leaking? Screws & vac line fitting tite on reg?
So after careful problem solving and deliberation, I the issue turned out to be the least expensive component.
The filters, thanks for all the feedback.
Additionally any adjustable fuel pressure regulator will leak down on a vacuum check due to the threaded adjuster nut. This is normal and is actually stated in the directions. I found this out after calling Aeromotive.
Appreciate the advice, I made sure all filters were in the right direction.
Additionally I know have Aeromotives Billet fuel controller hooked up. Let's hope for trouble free fuel control now.
I probably should have moved this to another forum, but I am now interested in a stock sumped tank. Anyone got one for sale or can help me out with getting one made up.
I have the old "Red" billet fuel controller Aeromotive makes... I had to purchase a MSD Tac simulator to get the Aeromotive unit to "See" the RPM..
Mine switches to high RPM fuel pump speed at 3200rpm
Before if I were to drive over 50mi even with full tank the pump would continue to get louder and louder... the fuel temps would be so hot the cell and lines would be almost too hot to touch!
I went on Drag Week last year... The last day was a scramble and little time to get fuel. I ran it down to damn near empty. I was sure the fuel was going to be at least warm with that little in the tank. WHen I got to the gas station the lines and cell were still cool. I was amazed. That Pump controller is amazing. And now the pump is silent.. it just purrs untill 3200rpm.
I am using teh same signal I am using to drive my tachometer. The only thing is I know you have to tell the tach whether the signal is coming from a 4 / 6 or 8 cylinder.
What is the easiest way to go about testing when the pump is going into high gear.
Voltage won't work - right because it pulses voltage but it is a 12 volt feed at all times - right?
