In-Line Fuel Pump Runs Continuously

87GNcospg

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Jun 23, 2003
I am working on a friends Turbo Trans Am that has a rough idle. While setting the TPS I noticed his in-line fuel pump runs continuously with the key on and engine off. It doesn't stop after it is primed. It will run for as long as you have the key on.
To my knowledge, this car still has the stock in-tank fuel pump and this separate in-line fuel pump.
I am assuming a previous owner was too lazy to replace the in-tank fuel pump for performance gains and just threw on an in-line pump to get extra fuel. I know the TTA fuel pumps are a pain to replace.

Is this common on TTA for people to keep the stock pump and put an inline pump?

There was a larger turbo, larger injectors and some other bolt ons previously on this car but we have put the majority of the stock components back on. The goals of the TTA are for it maintain slightly higher than stock horsepower numbers so the current fuel setup is ok for now other than it being extremely annoying with key on engine off.
I have included a picture of how the in-line pump is wired to one of the "IGN" slots on the fuse panel. Two splices coming off the fuel pump wire (after the fuse) are for the electric cut out and the greddy profec spec B II boost controller. All this was installed by previous owner.

What is the best thing to do here? Re wire the boost controller/electric cut out and hot wire the fuel pump? Is there another way to keep the pump from running continuously other than pulling it from the "IGN" slot like i have shown?

I do not have the specs on the in line fuel pump so i am not sure if this is just the basic design of the pump or if this is some sort of basic electrical stuff that i am missing.
 

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    TTA Fuel pump wiring.jpg
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If it were me i would leave the boost controller and cut out just the way it is. Take the T-taps off and put them on the other side of the fuse. then i would look for the fuel pump relay and connect an additional relay to control the new fuel pump. i just did a dual fuel pump setup with 2 aftermarket relays and works just like stock. If you need a diagram how to wire the new relays i could help if your not sure. pretty simple to install.
 
Is this common on TTA for people to keep the stock pump and put an inline pump?
This was one of the first methods used to increase fuel flow before there was a good aftermarket pump. It's still effective. Does the car have a hotwire?
 
This was one of the first methods used to increase fuel flow before there was a good aftermarket pump. It's still effective. Does the car have a hotwire?

It does not have a hot wire. Stock pump is wired as it was from the factory and the in line pump is wired as shown in the picture to the fuse panel.
 
It does not have a hot wire. Stock pump is wired as it was from the factory and the in line pump is wired as shown in the picture to the fuse panel.
Every car needs a hotwire to get good voltage to the pump. I would recommend getting one and then you could tee into the 12 volt wire that comes from the cars fuel pump relay which is used to activate a second relay that completes a circuit from the power output on the generator to the fuel pump. You could tee into this wire to operate a second relay that could also send good volts from the output lug on the generator to the inline pump.

You could also just tee into the good voltage coming out of the hotwire that feeds the in tank pump and connect it to the second pump.

The final thing that might work is that the in tank pump and hotwire and it's higher voltage might be good enough to supply the motor with the fuel it needs. If so you could eliminate the second pump.
 
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