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-   -   Aeromotive Fuel Problems...? (https://www.nopistons.com/single-turbo-discussion-13/aeromotive-fuel-problems-23666/)

rxrotary2_7 08-28-2003 08:40 PM

Scott,

first off... how have ya been? good i hope. https://www.nopistons.com/forums/pub...IR#>/smile.png

as you know, i also run the same pump. i do have a differnt EMS than you which plays *somewhat* of a role in this.... with the haltech is also primes the pump but as Jspecrace7 stated with the PFC the voltage is differnt due to the wiring from ecu to pump. volytage *could* be your problem, but i have a feeling your problem lies wiht the actual pump. if you notice, the pump will not hold pressure due to there being no *check ball*. if you notice, when turned off, imediatly if you check the guage, there should be zero presure. this is totaly differnt form the stock replacemt style pumps where they will hold presure.

also, did you build the start map from scratch? or using another mapas a starting point? your starting map areas could also be playing a role in some of the hard starting problems, but i have a feeling that after the pump ids primed, is where you problem may start....

btw, good to see you are making headway though. https://www.nopistons.com/forums/pub...IR#>/smile.png

88fc3sw/hx83 08-30-2003 02:17 AM

Lane change,

I've encountered a similar issue and I was running the Cosmo fuel pump. The problem is that the fuel lines do NOT stay pressureized after shutoff. To remedy this issue, people have recommended a check valve after the rails.



Jim

Dragon 08-31-2003 02:32 PM

The pump primes, but does it stay running once the car starts? You also really need to check your fuel pressure while the car is running. And did you hook up the fuel pressure requlator backwards, it wouldn't be the first time I've seen this done and have the symptoms your having..

lane_change 08-31-2003 08:27 PM

I just finished relocating my FPR to the front of the UIM so that I can monitor my pressure to see if that is the problem. How do you hook it up wrong? I have two lines in and one line out. Seems pretty straightforward to me.



I have checked the power and I have 12V going to the fuel pump controller, but I did not have a spare set of hands to check the pump itself when the key is on so it can prime. I will though.



I can hear the pump running when the car is idling and it idled for roughly 10 minutes the first time, before we had to shut it off due to temps....that is what I am trying to fix....but now I got to get her running again to fix that problem....so I now have two problems.



If it would just stay running long enough to build fuel pressure I am sure it would stay running, but it won't stay running any longer than 10 seconds or so.



Who knows....I will play with it some more and see why it won't stay running. It could be my maps, fuel pressure, pump voltage, etc....

pengaru 08-31-2003 09:37 PM

it sounds to me like you just need the pump to keep running not just prime and stop then start running again after it's started... if the pump doesnt have any check valve to keep the pressure in the system the 'prime' step is futile as the pressure leaves immediately after it stops priming. Why not just have the pump get 12V whenever the ignition switch is in the on or start positions?





if you would like to confirm your problem is that there is no pressure after it primes for starting, just put a battery in the hatch (for testing purposes) and wire it straight to the fuel pump.. then start the car... and troubleshoot your cooling system https://www.nopistons.com/forums/pub...#>/biggrin.png

Dragon 09-01-2003 04:34 AM

I used to have that Aeromotive pump in my car and it should pressurize the system damn near instantly with no problems. If it isn't then your pump is junk or you FP Reg is set too low or you need to adjust your fuel map.



I've seen people hook the in and out lines backwards on the regulator. Ie. fuel pump went directly to the out fitting on the regulator.



It should be hooked up somthing like this diagram

lane_change 09-01-2003 05:20 AM

I checked the voltage going to the Fuel Pump Controller. I have 17.2v going from my battery source to the controller...15.3v going to the pump.....17.2v going to the SWT.......and 0.0v going to the PWR.



I know my Voltmeter is a bit off, even though it is a brand new Craftsman, I should not have 17v from the battery, it should be 12v. Either way, you get an idea of what has power. These tests were done with the key in the on position, not with the car running, it may be different, but I can't start it to find out.



I tried swithcing the SWT and PWR wires around on the controller and on the relay....same results, PWR had no power and the SWT has 17v. I did not try switching the currents off of the ECU, could that be it? I wonder if the ECU wires are wrong....anyone know how they have their Fuel Pump Controller wired up?



Thanks,

Scott



Once I get it running again, I will check the fuel pressure and all that.

lane_change 09-01-2003 05:22 AM

Also, Dragon, nice pic....mine is set up right. I am running a -10 feed and a -8 return. There is no getting them mixed up under there.


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