4.6l 3V swap No Start Issue Bad PCM or Tune?

[Dman64]

Hi Everyone I am swapping a 4.6L 3V with manual trans out for a 2006 Mustang GT into my 57 Mercury truck and I am having a no start issue.

I could get it to stumble for 2-3 secs if I unplugged the Cam Position Sensors.

Engine is stock.
I have new ford racing 24lb injectors,
new plugs,
new coils,
new TPS,
New Crank Position Sensor,
New Cam Position Sensors,
Stock replacement MAF,
Air Raid intake tube,
Return style fuel system with in tank fuel pump wired independent of PCM. I have a mech regllator and 42psi of fuel pressure.
Harness is a 2006 harness that has been reworked by a guy who does this all the time.
Only running front O2 sensors
Stock Ex Manifolds,
No EVAP,
PCM has been tuned with HP Tuners. Pats has been turned off and confirmed.
I only had 3 codes. P0685, P0690, P1000.
I have purchase a second PCM and it won't run still. Oddly the accelerator pedal won't respond with the second PCM, we can see the voltage change when the pedal is pressed but the throttle body motor won't move.

I am at a stale mate. I have had a reputable tuner come out and review the set up and we have made some changes but we are still getting a no start or a stumble if we turn the fuel down so low that it shouldn't want to start but tries.

I have a voltage at the CKP and can see an RPM most of the time on the logger, my fuel injector pulse is sporadic with the Cam position sensors plugged in but with them unplugged it is steady.

I am starting to wonder if I have 2 bad PCM's or a compression issue or a bad wiring harness...I have pinned the harness out and don't see anything of concern. Engine suposedly only has 15,000km on it.

I'm at a loss. Any ideas or someone with a similar experience?

D

[decipha]

its a shot in the dark but try to start it with the maf unplugged just in case something is going on there

[momotunes]

With codes P0685 and P0690 it's mostly an issue with the harness. Either the wrong harness was purchased or the gentlemen who wired it up made an error. I think the years 06 to 07 had major differences in the ECM pin out. Also, I'm not 100 percent sure on that year but I do know that some Fords do goofy things when the EVAP switches are turned off.

I'd try what Decipha suggested first. If that doesn't work it's time to bust out the multimeter.

[Dman64]

Thanks for the suggestions. I have definitely done both of your suggestions. I have metered out every pin and they seem to check out. I am definitely questioning the harness at this point.

It almost seems like a timing issue. Anyway considering getting another harness and doing it myself this time and also buy a wiring service manual for the 2006 set up. I can get a used one for about $400.00CAD. Or I can buy a Ron Francis set up but it's just a bit pricier.

D

[Dman64]

With codes P0685 and P0690 it's mostly an issue with the harness. Either the wrong harness was purchased or the gentlemen who wired it up made an error. I think the years 06 to 07 had major differences in the ECM pin out. Also, I'm not 100 percent sure on that year but I do know that some Fords do goofy things when the EVAP switches are turned off.

I'd try what Decipha suggested first. If that doesn't work it's time to bust out the multimeter.

So I secured a second harness and ecm from a 2005 and the same issues are presenting. Wants to fire and sometimes it will but dies fairly quickly. Did some logging in VCM Scanner Fuel pressure looks good, I have RPM signal, I don't see anything for my MAF, but I'm new to this. Not even sure how to share my log file.

I do seem to get a lot of fuel and it is flooding the more I try to start it. I am running a return style setup and have adaptive voltage turned off. Do I need to adjust my Fuel Rail Set up? If so what and how do I do that?


D

[Dman64]

Log file

[B E N]

Verify your injectors are the 24lb to start, grab the part number off of one and double check. Load up a fresh stock 06' tune, then make sure the tables are updated as the frpp 24lb are different than the stock injectors. Go into fuel pressure settings and change everything to 42psi, does the airaid intake use the stock MAF? If it is a stock maf all you should have to do is update the fueling and it will run. If it doesn't you have a mechanical problem.

Here is a stock 06 tune.STOCK TUNE VERY IMPORTANT.hpt

[Dman64]

Verify your injectors are the 24lb to start, grab the part number off of one and double check. Load up a fresh stock 06' tune, then make sure the tables are updated as the frpp 24lb are different than the stock injectors. Go into fuel pressure settings and change everything to 42psi, does the airaid intake use the stock MAF? If it is a stock maf all you should have to do is update the fueling and it will run. If it doesn't you have a mechanical problem.

Here is a stock 06 tune.STOCK TUNE VERY IMPORTANT.hpt

I have the M-9593-LU24A Foord Performance Parts Injectors.

D

[Dman64]

Any chance someone can check my tune and see if my MAF and Injectors are set up alright?

D

[B E N]

https://performanceparts.ford.com/pa...m-9593-m23.pdf

That is the LU24 calibration from ford, doesn't match what you have. What is your MAF size?

[Dman64]

https://performanceparts.ford.com/pa...m-9593-m23.pdf

That is the LU24 calibration from ford, doesn't match what you have. What is your MAF size?

Mine are the LU24A. My CAI is 100mm and I have a stock MAF sensor.

https://performanceparts.ford.com/pa...9593-LU24A.pdf

D

[B E N]

Start with these values for your maf, your transfer is way off.

maf transfer 100mm.jpg

1.037563411
1.181499505
1.56144406
1.917642154
2.281415916
2.632952082
3.385993728
3.759382602
4.499458977
5.893657034
6.604596552
7.696791338
10.20625475
11.78236445
13.00355468
15.95678129
18.09056198
20.19472633
22.97767089
26.38458637
30.53142737
34.59902378
38.42124639
46.22263802
53.94831446
65.41529297
78.2755148

[Dman64]

What value are these in lb/min? Mine is in g/sec. The stock file you shared originally the maximum value shows up at 5V-300.

My HP Editor has a different scale.

lb/min grams/sec
1.037563411 7.843979387
1.181499505 8.932136258
1.56144406 11.80451709
1.917642154 14.49737468
2.281415916 17.24750432
2.632952082 19.90511774
3.385993728 25.59811258
3.759382602 28.42093247
4.499458977 34.01590987
5.893657034 44.55604718
6.604596552 49.93074993
7.696791338 58.18774252
10.20625475 77.15928591
11.78236445 89.07467524
13.00355468 98.30687338
15.95678129 120.6332666
18.09056198 136.7646486
20.19472633 152.6721311
22.97767089 173.7111919
26.38458637 199.467473
30.53142737 230.8175909
34.59902378 261.5686198
38.42124639 290.4646227
46.22263802 349.4431434
53.94831446 407.8492573
65.41529297 494.5396149
78.2755148 591.7628919


D

[decipha]

just take your whole maf transfer and multiply the y axis by 1.35 to add in 35% more air flow.

see if that gets you started.

the maf unplugged should have done the same thing though

[B E N]

Also you can change the units, just click on the green "g/sec" bit until its in the unit you want.

[Dman64]

just take your whole maf transfer and multiply the y axis by 1.35 to add in 35% more air flow.

see if that gets you started.

the maf unplugged should have done the same thing though

I understand. thanks.

[Dman64]

Also you can change the units, just click on the green "g/sec" bit until its in the unit you want.

I changed the values. I am also running metric and you are in imperial it appears, but all good. I will let you know what happens.

Thanks D

[Dman64]

Alright so installed tune and same deal turns over tries to start and doesn't quite catch. I have fuel, I have spark, My cam and crank are synchronized, I have made sure I get constant power at my injectors and coils in start and run. Made sure all grounds are good, I am truly at a loss.

My next steps are compression test first, then checking timing chain set up. I am missing something and just not sure what, then adventure continues.

D

[Adam L]

Any luck with resolution on the no injector pulse? I?ve got almost the exact same setup, 4.6L 3v stand alone harness, no fuel injector pulse unless the cam sensors are unplugged. Interested to hear if you ever got this one resolved. Cheers!

[Dman64]

Any luck with resolution on the no injector pulse? I?ve got almost the exact same setup, 4.6L 3v stand alone harness, no fuel injector pulse unless the cam sensors are unplugged. Interested to hear if you ever got this one resolved. Cheers!

Hi Adam, I do have injector pulse but what I'm finding is that my injector pulse width is very long, I am seeing 59-73 ms which is flooding my plugs and sometimes I get a backfire thru the exhaust due to the excess fuel built up. Eventually, the plugs get so wet that she doesn't want fire.

Do you have any engine codes?

D