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Old 05-01-2021, 07:21 PM
diaz1510 diaz1510 is offline
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Join Date: Sep 2018
Location: CA
Posts: 12
Default Finalizing install on a 3.5L Ecoboost, a few last questions...

Questions for @Richard_L but anyone knowledgeable, feel free to chime in.

It’s been a very long time and this project has been slowly coming together for over 2 years now, haha. I am finally at the point in my car build where all components, hoses, brackets and wires have been run and my very last step is to finally tap into the ECM wires. That is the absolute final step and I can begin testing and tuning the vehicle. But before I cut into the ECM wiring, I wanted to get some clarification on a few things.

I’ve included the drawing @Richard_L sent me last year so that we can be on the same page.

At the time, this was the only 3.5L ecoboost (transverse version found in the Explorer, Taurus SHO and Flex), so I understand there is some unfamiliarity with the platform. I have 6 questions that I am hoping can be answered:

1) Has there been any installations since this time for this platform and if so, are there any changes or revisions to the wiring I should be aware of since the v1 drawing I was sent?

2) I connected the RED WIRE of the Power Input harness to a switched 12VDC source but not from the ECM as pictured. Will that be an issue?

3) Please clarify what the purpose of the GREEN WIRE HARNESS is for as there shows no wiring for it in the drawing, however, it was provided in the kit I purchased. In “User manual v3.12 s/n:122228 on” it states this is for “DI INPUT and FLOW SENSOR SIGNAL OUTPUT”. I understand familiarity in the platform may be limited, but what would typically be required in an application that requires use of the green harness. It is a DI engine and my injectors are, in fact, peak & hold.

4) I notice in the drawing I am being directed to cut the PWM (-) “bridge” and solder to convert to PWM(+). What is this referring to? Is it the fuel injector signal wire polarity it needs to match? Generally speaking, what would dictate when to cut this and when not to?

5) The MAP sensor wire that we are tapping into…has anyone encountered any signal noise from doing this? I will defer to your expertise on this as you are way more knowledgeable, but I’ve heard from “internet experts (I mean that sarcastically)” that tapping into the MAP sensor signal line, for whatever reason, can sometimes introduce signal noise into the ECM and cause strange things to happen. Just would like an expert opinion on this.

6) As for the FRP wire, just to clarify, that is the Fuel Rail Pressure on the high pressure side after the High Pressure Fuel Pump (again, this engine is Direct Injection) that is being referenced, correct? It can see upwards of 3500psi or even more, in my application.

Thanks in advance. I'll include a bit of meth kit porn for those interested in my system.

Anyone interested in checking out the build, I frequent the SHO and Explorer boards and have a build thread. I'm mostly on the SHO boards:

Build Thread

And I also have an IG for those interested in following:


Last edited by diaz1510; 05-01-2021 at 08:38 PM.
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Old 05-01-2021, 08:02 PM
diaz1510 diaz1510 is offline
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Join Date: Sep 2018
Location: CA
Posts: 12
Default Re: Finalizing install on a 3.5L Ecoboost, a few last questions...

Just got clarification from XDI, the supplier of my injectors. I do have peak & hold injectors. This is per Uwe Ostmann at XDI:

"A port injector “peak and Hold Driver” is also not strong enough to drive DI injectors. Those are usually 8A/4A, for DI injectors you need 12A/8A/3A"

Does that mean I need to use the green harness? If so, how is the wiring specifically?

Last edited by diaz1510; 05-01-2021 at 08:07 PM.
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