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I did my harness myself, using a 2006 mustang donor car. I removed all of the unnecessary wires and ran power and grounds to the appropriate pins. I have a FPDM, but I am just using it to control a relay that activates my lighting fuel pumps (truck is on a 2002 lighting chassis) that go to a mechanical return style fuel pressure regulator. Other than that and removing the EVAP and downstream O2's/cats, everything else is stock. MAF, air box, injectors etc... all stock. the donor car ran great 2 months ago. I am planning to send my PCM out for testing next week, to rule that out. If it checks out maybe I'll try the stock mustang fuel system.
 

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When you added the FPDM, does your fuel pump run continuously with the key on? or does it shut off after a few seconds when the engine is not running? Mine runs continuously and I am told that is a sign of a faulty PCM.
 

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Great.... haha guess who I just ordered a PCM from. Oh well, we'll see what happens. It's crazy, there has to be at least a half dozen threads I've founds with almost the exact same issues. None of them have resolved it except one I saw where it actually was a bad PCM. Anyway, I have all of my grounds going to a stud welded to my inner fender right by the battery. Using the factory mustang battery cable which has two large ground cables, one goes to this stud, the other to the engine block.
 

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I swapped out my lightning pumps for the stock mustang PWM pump and ditched the regulator. So now I am 100% stock on my setup, besides exhaust and removing the EVAP system. I put the stock mustang tune in the truck, literally the only thing changed in the tune now, is disabling PATS... no change at all to what the engine was doing. Still fires occasionally and runs for 1-2 seconds then dies. For whatever reason the PCM is just not firing the injectors every time. Sometimes it gives one pulse when you start cranking, when it gets a pulse, it runs for just a second. Other times it will just crank and you get no injector pulse/no start.
 

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Well, I will second the poor service from flagship 1. I order a replacement PCM two weeks ago that was supposedly in stock. Called last week to find out what the status was. after waiting for about 20 minutes on the phone with an lady who could barely speak english, I was told it was "In processing" and I would be notified when it shipped.... Then today I get an email saying the unit is on back order.:unsure: So I asked them to cancel the order (hopefully I can get my money back) and ordered a PCM from another supplier. So hopefully I have a new one to try next week.
 

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Sorry to hear your bad luck, they really shouldn't be in business. If you can call your credit card company and say it never showed up, and cancel it. I had to call them multiple times a day and be a pain in the *** in order to get an RMA issued, and then they sent it after 3 months of hounding them. Once they got the bad unit back they never credited me and I had to dispute it with paypal.
The good news is, I did receive a full refund from flagship one!
The bad news is, I plugged in my new PCM today and there was no change to the symptoms:cautious:
 

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There are, what Greg Banish at Calibrated Success calls, Universal Truths, if I remember correctly. Two of them are excellent grounds and adequate voltage. Something you should know is battery adequacy is neither measured nor determined by when you bought the battery. Battery adequacy and for that matter electrical system adequacy is measured by power available at the battery and in the car.

A good, charged battery should show between 11.9 to 12.5 volts at the battery, the higher the voltage the better. A good electrical system in a running car should show between 13 and 14.2 volts. If your numbers fall outside those guidelines you need to find out why and fix it.


Ed
I agree good grounds and adequate voltage should always be the goal, but in my case (and I believe the OP is in the same boat) we are not even getting the engine running long enough to activate the alternator. with the voltage drop from the starter 11-12 volts while cranking should not be an issue.
 

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Has anybody on here successfully swapped a 3v into something else using the stock PCM/Harness, or a Ron Francis? I am at a loss of what to try next. Could there be something in the cluster/BCM/PATS/other modules that the PCM needs to see?

After doing some more research, unplugging both cam sensors puts it into some sort of "failure" mode and will then fire the injectors and spark on both cycles, thus why it will run for a couple seconds but has a bit of a misfire. Also to note, with the cam sensors unplugged, I can press the gas pedal and get a response (engine revs like it should). It still shuts off after about three seconds though.

with the cam sensors plugged in, it will only run for about a half second, and has no response to the throttle pedal.
 

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hopefully between the three of us, somebody can get this figured out... I've been working on paint/interior and wiring the rest of the truck, but hoping to start trying to get it running again soon. My 06 also does not have anything in pin 46. I believe that pin was used on the 07 up models. Looking at my wiring diagrams the 1140 circuit is the "Run" circuit that triggers all of the PCM/ fuel pump etc... relays. Are you guys using the factory "BEC" (fuse/relay box)? I am not.
Previously I had all of my grounds going to a single stud. My plan now is the separate some of the ground circuits to be more like the factory. Specifically all the the (570) black/white grounds. I will splice them all together and terminate them to a different location than all of my generic grounds. Same thing with the 1118 power circuit for the coils/injectors/pcm. I will splice them all together this like the factory was. Other than that I really don't know what else to try. I'm really wishing I would have just went with a coyote at this point.
 

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So I started working on the engine again today. I changed the ground circuits a little bit to match the factory (isolated the Black/White 570 ground circuit) and that didn't change anything. So I swapped in another harness that I picked up a while back. Also no changes. I did get another ECU with the harness, but at this point I'm not sure I want to spend the $100 on credits to tune another ECU to remove PATS. I'm close to throwing in the towel as well, and dropping in a Coyote .... or even a 2V in this thing.
 

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I am bailing on the 3V as well. I picked up this beauty for a few hundred bucks at the local copart. 2011 with under 100k miles. If I had the time, I'd do a stand-alone. But for the time and budget of this project, it doesn't make sense. I bought this entire car for less than the cost of a standalone system.
Car Automotive parking light Automotive side marker light Tire Land vehicle
So if anybody needs an 06 PCM or harness, I've got two of each.

On a side note. I've already got the 3V mustang gas pedal mounted in the truck. Any body know if the mustang and Crown Vic pedals are interchangeable? Looks like the same connector.
 
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