Fuel pump help - LS7
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Fuel pump help - LS7
I bought 06 Z06 in Dec. It has a Aeromotive Eliminator external fuel pump. I had a failure of the pump or system. There is no power to the pump, if I direct wire it will work. My 1st concern is there any need to drop the tank for any reason. Would the in tank pump not been disconnected or removed with the installation of the add-on external pump. I think it is a relay issue, not sure though. The failure began with missing and sputtering under acceleration. Then after turned off and engine cooled no fuel at all. Would not start.
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Lessen learned a long time ago with the 924's vapor locking, you need to have a fuel pump in the tank pulling fuel to begin with. Now if you need more pressure/volume, then you can add an additional pump in line to increase the pressure/volume to the fuel rail instead.
The second way to increase the volume of the OEM fuel pump is to add a BAP, which increases the voltage to the fuel pump, but it just burns the fuel pump out faster isntead. Worse if you let the fuel gauge get under 1/4 full, since the pump submeriged in fuel help to cool it, and with the pump no longer submerged with the tank low on gas, the pump is going to over heat quickly as it being over spun.
As for your problem, would double check the wiring of the pumps, and make sure that someone did not try to wire in the new pump using the OEM wiring from the Fuse box to the tank instead.
Hence the fuse box fuel pump relay wiring 12v wire is only used as a trigger wire for an in line SPST 30amp relay so the fuse box/fuse box relay/fuse box wire is only seeing about 450ma when it triggers the secondary relay (relay is pulling it power directly from the battery with it own inline fuse), and then both the new in line pump and even the tank pump are wired to relay for power instead. In regards to both fuel pumps, they are both wired to the secondary relay, and regards to the fuel pump in the tank, it wired off the secondary relay, with a wire of the correct gauge size run from the secondary relay to the wire connect at the fuel pump (not back up at the fuse box wire isntead).
So again, would bank that someone tried to use the OEM wiring from the fuse box to the tank to drive both pumps,that wire is under sized gauged for such use, and someone in the middle of the wire line between the two, the wire burnt up/ heat cracked instead.
The second way to increase the volume of the OEM fuel pump is to add a BAP, which increases the voltage to the fuel pump, but it just burns the fuel pump out faster isntead. Worse if you let the fuel gauge get under 1/4 full, since the pump submeriged in fuel help to cool it, and with the pump no longer submerged with the tank low on gas, the pump is going to over heat quickly as it being over spun.
As for your problem, would double check the wiring of the pumps, and make sure that someone did not try to wire in the new pump using the OEM wiring from the Fuse box to the tank instead.
Hence the fuse box fuel pump relay wiring 12v wire is only used as a trigger wire for an in line SPST 30amp relay so the fuse box/fuse box relay/fuse box wire is only seeing about 450ma when it triggers the secondary relay (relay is pulling it power directly from the battery with it own inline fuse), and then both the new in line pump and even the tank pump are wired to relay for power instead. In regards to both fuel pumps, they are both wired to the secondary relay, and regards to the fuel pump in the tank, it wired off the secondary relay, with a wire of the correct gauge size run from the secondary relay to the wire connect at the fuel pump (not back up at the fuse box wire isntead).
So again, would bank that someone tried to use the OEM wiring from the fuse box to the tank to drive both pumps,that wire is under sized gauged for such use, and someone in the middle of the wire line between the two, the wire burnt up/ heat cracked instead.
Last edited by Dano523; Apr 26, 2018 at 10:50 PM.
