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Discussion Starter #1
Hey all,

Yes, I read the stickies.

I got a boost a pump and wanted to check on an as-yet-unresolved issue with the BAP installation.

1) Is it imperative that you install the positive of the boost a pump in between the ECU and the fuel pump module, or between the module and the pump itself, or either (does it matter?)?

2) What is the "S" wire for?

3) what did everyone use for their ground?

My current setup is as follows:

-Red wire from BAP w/fuse goes toward the ECU (positive wires are between the ECU and the fuel pump module).

-Red wire from BAP without fuse goes toward the fuel pump module.

-The above wires are both spliced into the orange and green wire (mine is a zetec, but I was given instructions from someone that had an SVT...is this the right wire?).

-Ground wire is connected to a ground on the side of the seat support, another wire was already grounded there so I figured this was satisfactory.

-Left-over cable ("S" cable) is not connected to anything. Should it be?

I don't believe its working right now because the pressure drop across fuel injectors (SCT datalogging software) measures 40psi at idle and at 15psi boost is at 31psi still. This is the same that I saw pre-BAP. What PID should I use to figure out the voltage?

Thank you in advance for your help.

--Matt--
 

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Hey you wire it up between the fuel pump and fuel pump modual also i grounded mine to the seat belt
 

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Discussion Starter #3
I'm gonna wait to switch the line around, but thank you for the suggestions. I'll move the ground when I have a chance but I want to wait for others inputs about the wire splice location--orangesvt03 said his was between the ecu and FPDM and worked fine, and the kid I bought the BAP from told me to put it there as well...hmm...

MOAR INPUT!!!! ;)
 

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Yep... mine goes ECU-> BAP ->FPDM -> Fuelpump

I grounded it to one of the bolts under the back seat.... and it has worked flawlessly since I put it in.
 

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Discussion Starter #6
So, that "S" cable...does that do anything?

I'll try changing the ground but I was assuming because the ground I used was being used as a ground for something else that it'd be effective...My bad, haha...
 

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I installed mine between the FPCM and the fuel pump as Tom suggested. Seems to work fine for me. My fuel pressure is close to 40psi at 18psi of boost.
 

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Discussion Starter #8
Hmm....maybe I can hook the fused positive and the ground to a car battery and see what the output at the other red wire is, see if it fluctuates when I turn the knob up and down. If that works then I know it's a wiring/grounding issue.
 

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Discussion Starter #10
Which PID are you using, pressure drop across fuel injectors? I just know that I did a quick second gear pull and the fuel pressure dropped off to 31psi as it was before I started using the BAP. This was with the BAP on the 25% overdrive setting (pump should see 15v and resultant pressure should be 50psi, each 10% overdrive adding another 10% of original pump's output).
 

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yes pressure drop across fuel injectors
 

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Which PID are you using, pressure drop across fuel injectors? I just know that I did a quick second gear pull and the fuel pressure dropped off to 31psi as it was before I started using the BAP. This was with the BAP on the 25% overdrive setting (pump should see 15v and resultant pressure should be 50psi, each 10% overdrive adding another 10% of original pump's output).
Matt, even with my BAP up to the max, I still only get around 40psi in the upper rpms. I don't think you'll get any better without a return style fuel system. Yes, fuel pressure drop is what you need to look at.
 

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Discussion Starter #13
I know Tom mentioned something about grounding being a real issue not only with the BAP but with the fuel pump itself as well. I'll try turning the BAP up more and looking more closely to datalogging. I'm at 15psi now and probably 260hp or so, I'm guessing you are higher William--I just didn't know why it made no difference whatsoever turning the BAP to 25%. I'll max it out in my next datalog and see what it does.

Now that you mention it, the lowest pressure on this past run was 31.3psi as opposed to the 29.8 I got last time, but that may also just be because this run was a quick 2nd gear pass as opposed to the 3rd gear the previous time.

I'll try changing the ground location, soldering the wire connections (right now they just have wire nuts on them) and maxing out the BAP.
 

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John also has the little cheat thing that makes his fuel psi crazy good. its not a cheat but he changes somethinng in the tune and it becomes really high
 

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Discussion Starter #16
And he has a SVT fuel tank, pickup, and pump--that makes a pretty considerable difference AFIAK. I just have a 01 focus with the 01 tank, the post-recall pump (which I had to install myself since ford wouldn't admit that I have one of the affected pumps GRRR) and the boost a pump. I just want to maintain 40psi as islandfocus is in the higher rpms, but am not sure if that's possible at 22-25psi of boost. We'll see.
 

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I maintain 62psi of fuel at 7k rpms @ 19-23psi (when the cars running)

Without a BAP on a Zetec I can hold around 50psi of fuel at 6500rpm and 12psi.... its all in the tune.
 
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