Mustang and Ford Performance Forums banner
1 - 20 of 20 Posts

·
Registered
Joined
·
25 Posts
Discussion Starter · #1 ·
Hi Everyone. I am doing a 4.6l 3V swap from a 2006 Mustang GT into and old truck. I have the stock harness and pcm which has been re pinned and reprogrammed with HP Tuners. PATS has been turned off, this has been confirmed.

I can't get it to stumble sometimes but not all the time.

I have Crank Signal and Spark while cranking.

I have 12V to my injectors in key on and while cranking.

When I starting cranking upon a new key cycle I get one pulse with 1 shot of fuel.

If I connect my test light to the control side of the injector and battery positive I get one pulse while cranking then nothing.

I have a stand alone fuel system and an adjustable regulator that is set to 42psi and it stays constant while cranking.

I have new coils, New Plugs. Injectors do test out with a 9V battery. I have 5V reference at MAF. MAF is stock replacement.

I have checked grounds on connector C175T and have continuity on pins 10, 47, 48, 49, 50.

I have disconnected all injectors and ohmed them out to confirm that nothing is shorted.

Not sure what tells the injectors to fire or what is failing in the sequence. Any help would be appreciated.

TIA D

- - - Updated - - -

Sorry not sure how to edit thread. But I CAN get it to stumble randomly if I can get fuel in it.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #5 ·
I bought this set up 4 years ago and have never heard it run. I had a guy who does these swaps rework the harness and re program the ECU. I do have a new set of injectors coming fearing it was a shorted or plugged injector.

I messaged him and he took another look at the program and said there doesn't seem to be anything out of sorts. The guy doesn't live anywhere near me and the engine is sitting in my 57 mercury truck so there is no going back to a stock tune. All parts are stock on the engine except for the CAI but I used the stock MAF. The MAF is facing the correct way and has 5V at it as well as 12V.

I agree it is a fuel delivery issue but it's a matter of going thru some tests with a proper scan tool attached to see if we are missing anything or if a sensor is out of whack.

I wouldn't rule out a damaged harness but it was gone over so I assume it good. Not sure what ohm values I should be looking for if I am looking for a shorted or damages harness.

I could send the ECU to get tested and see if it is a bad unit but not 100% sure were to send it. I want to start with the cheapest and go form there if that in fact makes the most sense from a trouble shooting stand point.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #7 ·
It's interesting that you say that as I had a local guy who is a tuner come over and he hooked up his laptop and HP Tuners and went thru it all and felt that it looked good. I have been tested the TPS and MAF and FPS for voltage VREF and grounds and they seem good. Still at a stand still. May have a local AutoTech electrical guy come over and have a look and give his opinion.

Once I find the solution I will share it.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #8 ·
Ok I have an update in that is going in the right direction. I replaced my injectors as this engine is 13 years old and has been sitting at least 4 or more years, definitely got more of a stumble out of it.

Did a bit more reading and decided to unplug the Cam Position Sensors, she fired right up but dies after 3 secs. Fuel pressure remains constant and within factory specs. I tested my injector pulse and it seems to be more present while cranking. I think I will change my Crank Position Sensor and the Cam Position Sensors. They are $111 CAD for motorcraft brand from rockauto. Parts should arrive Friday and I will give it a shot.

I did only get 180mVAC when back probing my Crank Position Sensor, and from what I understand I should have 500mVAC to 1VAC.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #11 ·
I know. I was talking with a Ford Tech today and he mentioned maybe that the engine isn't seeing power in the run position once it fires. So just to confirm 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 and I never lost the voltage once. My process to getting this thing running at this point is. So for me it technically rules that out unless there is and internal PCM Issue.

1) Change CKP and both CPS.
2) Getting alternator tested to make sure the rectifier bridge isn't broken and causes weird feedback voltages to the PCM.
3) Sending PCM out for testing to make sure it's not the issue.
4) Ford Racing timing set with new cam phasors, chains etc. This is a very last resort.

I did find another thread in the 2005-09 ford that 2 guys had the same issue, one never posted his resolve and the other said his PCM was bad and he replaced it and good to go.

https://www.modularfords.com/threads/195230-Putting-the-4-6L-V8-into-someting-else-Need-PCM-help

https://www.modularfords.com/threads/239609-3v-swap-No-start/page2?highlight=zzkats

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #14 · (Edited)
Ok so CKP changed along with CPS and same result. It will only fire with both CPS unplugged. Popped off right valve cover to inspect Cam Phaser and VCT solenoid, both look to be in very good condition. Nothing seems out of sorts.

I recently did a 5.0 Explorer EFI swap into a '68 F100. Some of the power to the PCM is always hot (B+) and other parts are powered only in the run position. Initially I wired the run relay trigger to the accessory/run lead coming off of the ignition switch but came to find out that it lost power while the ignition switch was in the crank position. That confused the PCM greatly. The engine did a lot of what you are describing.

Your old fender mount starter relay has 2 little wires coming in to the top. One is the starter wire and the other labelled I(?). It originally powered the coil with 12VDC while it was cranking. I took that power over and tied it into the one from the ignition switch run/accessory.
I did connect my DMM a to confirm and had 12V to the correct pin and 12V consistent in start and run while cranking and had anywhere between 10.66V to 11.65V while cranking, no voltage was lost during or after cranking stopped.

I had a similar issue with a 03 Cobra swap and was chasing my tail. I found there was a crossed wire on the modified harness. I would do a point to point check on your harness.

Also, is the ECM setup for a return type fuel system?
I have been considering getting my knife out and cutting some tape to inspect. I have done some continuity and pin testing and haven't found anything strange yet. All injectors pin to correct injectors and pins as well as coils and in the correct firing order as well. But a quick inspection maybe in order before I send my PCM out for testing.

Next test is disconnecting the alternator to see if isolating it from the PCM changes any behaviors. Just not sure why unplugging the Cam Position Sensors allows it to start to me that smells of bad wiring or PCM issue.

Thanks for all your input!

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #15 · (Edited)
I'm still chasing my tail on this one. I have tried another harness and ECM and have the same end result. It wants to run but it seems to fire and then dies. IF anything it seems like it gets to much fuel and floods itself out. I do have a return style fuel system what do I need to do other than turn adaptive voltage to disable? Do I need to tune my fuel rail setup? If so how do I do that?

Engine is all stock except Airaid CAI with stock MAF.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #17 ·
I don't have an inertia switch yet. I have a 15A feed powering an in tank pump that feeds a mechanical adjustable regulator set to 42psi with vacuum line disconnected, fed with 3/8" lines. It is a return style set up. I can hear the fuel pump running and know I have fuel as I think I may be flooding from too much.

Maybe my return style set up isn't set up properly in HP tuners. I have it set to adaptive fuel disabled, but haven't adjust the fuel rail psi set up or anything else.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #20 ·
disregatd, i think mine was wiree differently.
No worries. Mine has a stand alone set up right now. I have an intake fuel pump that is controlled when the key is turn on a relay engages and turns the pump on, it then runs constant. Fuel pressure is controlled by the mechanical regulator.

The system is a return style so I have turned fuel adaptive voltage control off in HP Tuners. When I scan the start procedure I have constant fuel pressure as I monitor the Fuel Rail pressure transducer and it is definitely showing pressure.

After 15 min of trying to start it I usually need to stop as the plugs are wet from fuel so I definitely have fuel. If I hook up a timing light and monitor the control wire on the coil it does flash as I crank it over, so I have spark.

It seems like it is either a incorrect timed procedure or power to the ecm is shutting off somehow or it thinks it is shutting off. I have used my DMM and monitored voltage and even monitored it in Forscan and it seems to be there while cranking, KAPWR is yes, Cam and Crank are synchronized while cranking. I'm at a loss.

D
 

·
Registered
Joined
·
25 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
·
25 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
·
25 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
·
25 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
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #42 ·
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.
Finally, here it is giving it some throttle with the cam sensors unplugged
There is a guy that put one in a ford ranger and he used Ron Francis wiring harness.

Why is it that when you make it go into a default mode by unplugging a sensor it will run longer? It makes no sense. It's like there is maybe a wiring piece missing? It's almost like the key gets shut off or the timing table is confused.

The cam sensors control PWM for the injectors, if I remember correctly. So why do we lose the injector pulse? The injectors are 12V constant and the ground is controlled by the ECM, so where is the break down?

BTW glad to hear you got your refund.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #45 ·
Welcome to the club, sorry. A couple of questions for you. 1) What year PCM do you have? 2) Do you have any engine codes?


I wonder about wire 1140 Pin 46 in harness 175B, mine has no wire there and is the ISP-R location. This is to be hot in start and run, and is what is tied to the fuel pump relay coil hot side when the key is turned on.


It's almost like it fires and then shuts off, but the fuel PW is way too high and is flooding the cylinders so the PCM shuts it down to prevent cylinder wash.

This is kind of where I'm going next.

D
 

·
Registered
Joined
·
25 Posts
Discussion Starter · #48 ·
Mine doesn't have Pin 46 either but maybe that is the piece we are missing. Once you modify it from the factory setup this may be required. The setup is acting almost like start and then shut down, but why? At this point, there have been multiple harnesses and PCM's tried by all of us and we are in the same place, I think that Pin 46 is worth considering.

Ford Racing swap harness and PCM uses a 2007-2009 engine harness and incorporates Pin 46, I would think that 2007-2009 uses it as well, in the factory setup.

I may be wrong but I think it's worth a shot.

D
 
1 - 20 of 20 Posts
Top