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Discussion Starter · #1 ·
Just finished and test fired with a Fore twin pump and ID1300s. I bought a fuel pressure sensor extension from Dave Steck, plugged into the factory harness at the original pressure sensor location, then run up to the new sensor on the Fore filter. The car runs. It's getting pressure, but the aeroforce is showing 0.

I tapped the green/white wire from the FPCM to trigger the fuel pump, and a hobbs switch to trigger pump 2.

Is there something i need to bypass or disconnect to get my fuel pressure reading to the ECM/aeroforce?

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Discussion Starter · #3 ·
FPCM is still fully connected, nothing is changed with it, except that there are no pumps connected.

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Discussion Starter · #4 ·
I even tried connecting a spare pump hat to see if it's some kind of logic system, to no avail. I can't think of anything else, short of a bad cable extension. I'll check continuity on the terminals tomorrow.

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So just to get the obvious out of the way, is the sensor plumbed into the feed line or return line?
 

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Discussion Starter · #6 ·
Haha it's definitely in the feed side. I put a mechanical gauge on the regulator and set the reg to 60psi. There's pressure on the line, but the signal isn't making it through to the pcm for some reason. Or at least not making it to the aeroforce.

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Then maybe something wrong with the new sensor or wiring? Have you logged it with HP tuners? Btw, I have a Squash system and kept the pressure sensor for logging and it works fine.
 

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Flex sensor goes on the return side, I think.


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Discussion Starter · #9 ·
Flex sensor goes on the return side, I think.


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That's where I've got it, it's post-regulated, then into the flex sensor, then back to the tank.

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Discussion Starter · #10 ·
Then maybe something wrong with the new sensor or wiring? Have you logged it with HP tuners? Btw, I have a Squash system and kept the pressure sensor for logging and it works fine.
Did you keep the fscm?

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dont put the flex on the return line it will read different ethanol % based on the amount of fuel going over it so will be change fueling all the time, i was tuning one a while back and under a full boot less fuel would go thru and it would change like 40% lower in ethanol content (which means leaner ) if ur doing a long hard wot run and its enough time for it to correct the AFR it could end bad, on feed line it wont restrict anything works fine
 
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Discussion Starter · #13 ·
I finally got back to work on the V, I'm not getting a 5v signal to the sensor. I checked at the FSCM, and the brown wire is not outputting 5v. I swapped out a spare FSCM, no change. I've tapped the green/white (ecm) wire that goes to the FSCM to trigger my primary pump, as recommended by Dave Steck in an older post. Is it possible that triggering from that is screwing up the fscm signaling?

Any inputs appreciated.


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I finally got back to work on the V, I'm not getting a 5v signal to the sensor. I checked at the FSCM, and the brown wire is not outputting 5v. I swapped out a spare FSCM, no change. I've tapped the green/white (ecm) wire that goes to the FSCM to trigger my primary pump, as recommended by Dave Steck in an older post. Is it possible that triggering from that is screwing up the fscm signaling?

Any inputs appreciated.


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May I confirm what wire you run the sensor wire too on the fpcm?

And does a standard 0.5-4.5 sensor 100psi sensor work or do you need a specific sensor and range to work with the fpcm?
 

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May I confirm what wire you run the sensor wire too on the fpcm?

And does a standard 0.5-4.5 sensor 100psi sensor work or do you need a specific sensor and range to work with the fpcm?
The fscm is going to want a sensor with the same parameters as stock (unless this can be flased? not sure...) The stock sensor is not expensive. Where is your factory sensor and wiring to chase?
 

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The fscm is going to want a sensor with the same parameters as stock (unless this can be flased? not sure...) The stock sensor is not expensive. Where is your factory sensor and wiring to chase?
after a little more thinking, I think this is the route I am going to take, put a factory sensor back on it (will be up at the front of the car) and just extend the main harness up front as well. Then I can just run the fpcm parameters as you said. Thanks Adam!
 
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Does anyone have any feedback on this? Running the FPCM just to get fuel pressure through the ecm?
 

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Does anyone have any feedback on this? Running the FPCM just to get fuel pressure through the ecm?
Yes, I do this. I purchased the GM fuel pressure 6AN adapter fitting and use it on my feed line. I extended the electrical connector by soldering in more wire and it works perfect.

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So leave the FPCM plugged in, just turn off any communication codes that show up?

This thing already had the FPCM unplugged and the Squash kit was using the switched 12v wire to run them.

The ALM hat I have has a fitting in the lid and an 18" hose to screw the pressure sensor in to. I bought a sensor and currently have it in that line, just need to plug it in and try to see what happens when I hook the FPCM back up, then.
 
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