Mustang and Ford Performance Forums banner
21 - 40 of 49 Posts

·
Registered
Joined
·
23 Posts
Discussion Starter · #22 ·
I have not. I have added a FPDM and swaped my fuel pump out for a PWM pump and It still starts and stumbles until it floods out eventually. I am going to confirm proper grounding and that my fuel tables is adequate.

I had another guy contact me about 2 months ago with the same issue. I have also spoken with Art at wire diet and what he tells me is that the 3V is very finicky and it wants a stock fuel system or you need s tuner that can really tune your STFT and LTFT tables.

Not sure if that helps. Did you work your harness or get someone else to?

D
 

·
Registered
Joined
·
13 Posts
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.
 

·
Registered
Joined
·
13 Posts
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.
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #25 ·
My new fuel pump is pretty quiet so it's hard to say. I doubt your PCM is faulty, I tried 2 separate harness and PCM's one from 2005 and one from a 2006 and have the same issue. It has to be something simple, but I refuse to give up :) What ever you do stay clear of FLAGSHIP 1, Crap Products and 0 customer service.

D
 

·
Registered
Joined
·
13 Posts
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.
 

·
Administrator
1965 SPF Terminator Powered 427 Cobra, & 2022 BMW M850
Joined
·
9,490 Posts
I went back and reread this thread from the beginning, again. Early on in post # 11 you say,
...I hooked up my DMM to the relay that controls those power feeds and I consistently see 11.41VDC give or take when cranking. Lowest I saw was 10.66V...
That is somewhere between marginal and inadequate. Generally the low water mark for power and sustaining engine operation is around 11.5 volts. At 11.5 volts you are out on the thin ice so to speak. A good alternator should put you somewhere betweel13.5 and 14.2 volts with the engine running. Your battery needs to be able to supply you with a good solid 12 to 12.5 volts during cranking. If the battery is good and it can not, then you may have power or ground connections that are marginal.

Power conditions not withstanding I am still very suspicious of the tune. Can you put the tune back to a 100% stock, as delivered by Ford, tune and use an umolested stock ECU to attempt to start the engine. If it starts up then you either have a bad ECU or a screwed up tune, possibly both.

An alternative approach would be to dump the OEM ECU and go with an aftermarket ECU, which brings with it a wide range of additional good karma — not to mention tools and features.
 

·
Registered
Joined
·
13 Posts
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.
 

·
Administrator
1965 SPF Terminator Powered 427 Cobra, & 2022 BMW M850
Joined
·
9,490 Posts
OK, now do you have access to an untouched OEM ECU to susbstitute for the ECU to see if the problem is the ECU?
 

·
Registered
Joined
·
13 Posts
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.
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #32 ·
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.
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.
 

·
Registered
Joined
·
23 Posts
Discussion Starter · #33 ·
I went back and reread this thread from the beginning, again. Early on in post # 11 you say,


That is somewhere between marginal and inadequate. Generally the low water mark for power and sustaining engine operation is around 11.5 volts. At 11.5 volts you are out on the thin ice so to speak. A good alternator should put you somewhere betweel13.5 and 14.2 volts with the engine running. Your battery needs to be able to supply you with a good solid 12 to 12.5 volts during cranking. If the battery is good and it can not, then you may have power or ground connections that are marginal.

Power conditions not withstanding I am still very suspicious of the tune. Can you put the tune back to a 100% stock, as delivered by Ford, tune and use an umolested stock ECU to attempt to start the engine. If it starts up then you either have a bad ECU or a screwed up tune, possibly both.

An alternative approach would be to dump the OEM ECU and go with an aftermarket ECU, which brings with it a wide range of additional good karma — not to mention tools and features.


Ed

I am working on making my wiring more permanent as I complete my bodywork, as I put things back together. I have updated some serious ground straps and am starting to isolate them to keep the resistance low. I have run a decent size wire and ground block from the battery to beside the ECM and will connect the 5 grounding pins here, rather than connecting to the frame. My battery is definitely adequate as I have purchased a new unit and I have even removed the clutch to ensure no additional drag when hitting start.

D
 

·
Administrator
1965 SPF Terminator Powered 427 Cobra, & 2022 BMW M850
Joined
·
9,490 Posts
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.
 

·
Registered
Joined
·
13 Posts
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:
 

·
Registered
Joined
·
13 Posts
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.
 

·
Registered
Joined
·
13 Posts
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.
 
21 - 40 of 49 Posts
Top