Help 5.4l gt509 control pack no higher than 3900rpm

[Mock4147]

Hello members I have a 1967 f100 pickup truck with a 2007 gt500 engine and trans and the ford racing 5.4l control pack with pcm and wiring. The engine has the following mods
Vmp gen II-R tvs
Id 1000 injectors
2.4 upper pulley
10% lower
Twin 67mm throttle body
Jlt cai
170 thermostat
Vmp triple pass dual fan heat exchanger
Fore invocations return fuel system with twin 465 pumps

The truck ran great on pump gas tuned my vmp
I switched to e85 and it ran fine I drove it down to event vmp was at and had them finish the e85 tune on the dyno it ran fine getting 721rwhp and 695 torque

On the way home from the event the truck would no go over 3900rpm. This happens in every gear as long as I shift before 3900rpm truck runs fine but once I hit 3900rpm the truck fall flat on it face like it it a brick wall leans all the way out and won't go past 3900rmp

I have checked everything I can think of I had vmp look at tune and all looks good. I called fore innovations and the fuel system is performing great. I switched backed to 93 octane tune and still will not go past 3900rmp. It is like the engine goes into limp mode but that feature is not programmed into the pcm on the control pack

On the data long everything looks good accept the maf count does not move I have changed the maf and no difference. I called ford racing and they are looking into it but I was hope someone here has had the same problem



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[RedVenom48]

What are you using to tune the car? Does it feel like its hitting a rev limiter?

Double check the tuner and make sure that the RPM limit is set to 6250-6500 RPM. Are there any codes in the ECU? Have you tried reflashing the tune?

 

[Mock4147]

What are you using to tune the car? Does it feel like its hitting a rev limiter?

Double check the tuner and make sure that the RPM limit is set to 6250-6500 RPM. Are there any codes in the ECU? Have you tried reflashing the tune?

Using sct x4 as a tune device and yes fell like hitting limiter. And the codes I'd is throwing is p0453 evap p0462 fuel sender p1234 fuel pump driver module and the p0102 maf low voltage. The first three should not even come up on a control pack because they are turn off when the pcm is ship from ford racing I have a call into ford to see why they are coming up because I have a stand alone fuel system and the maf code show up because the maf count never changes but I have checked the maf connection and have changed the maf

Yes have tried to reflash the tune several times I even drain all the e85 and went back to 93 tune when it was running fine and still does it so I don't think it is in the tune


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[RedVenom48]

If it was running fine before but after the dyno tune and now its not, my opinion is that its something in the tune. Agreed that those codes shouldnt be popping up.

P0102 could be whats throwing everything off. Possibly a failed MAF and its in limp mode because of it. Check the connector for corrosion or anything that looks abnormal. Also the P0462 and P1234 could have a limp mode enabled condition as well. But, since youre on a control pack with stand alone fuel system, those parameters shouldnt even be on. This is now just pure speculation on my part, but its possible the tune got set up at the dyno with GT500 parameters so its looking for FPDM and sender signal for a 2007. Obviously there is no such provision on a custom build as yours.

Your BEST bet is to data log with the X4. Email VMP and ask them for their data log config file and load it into the x4. Ask them what kind of drive cycles they want to have you do.

Ford may also have some parameters they want on or off going forward.

Sorry this is happening, sounds like you have a bitching F100 there!

 

[Catmonkey]

This is just a thought, but the low MAF voltage got me wondering what sort of voltage is you alternator putting out? All sorts of electrical gremlins surface when low voltage is powering the sensors and the PCM.