Anybody worked on a flex fuel PCM?

[Upgrades]

I was driving home a couple weeks ago, my flex 3.0 lost a lot of power, started shaking, and the engine light came on. I was less than half a mile from home and took the chance and managed to get it parked at home.

Long story short, I got it towed to my mechanic, since I have little experience with engines. He tells me that the IGNITION COIL DRIVER in the PCM has gone bad. He says there are 3 drivers, each fires a pair of coils, and ONLY ONE of the drivers in the PCM has gone bad.

He says I have to buy a new computer for the 3.0, and if it is not already programmed for the FLEX 3.0, that Ford will have to flash it.

I have some pretty extensive electronics experience, and was going to make an attempt to open up the PCM and see if I can repair it.

Before I move ahead with this endeavor, I wanted to see if anyone has ever experienced something similar and has any advice, schematics, or any other resources to make this easier for me.

I know everyone is going to say to replace the coils and I am going to do that as soon as they arrive. I trust this mechanic, although he could be wrong, I just don't see why he would want me to buy a computer from someone else and pay Ford to flash it if it's not actually the problem. I mean what does he have to gain from that?

 

[RonD]

Check the codes in the PCM, they should still be there in History or start engine and CEL should come on again, with current codes set.

Yes, PCM needs to be for Flex fuel in your year, Ford removed the Fuel type sensor on the fuel line in favor of a PCM software upgrade.
Flex fuel engines use larger fuel injectors so they can pass more fuel when using E85 without setting a code.
A non-flex fuel PCM would have to shorten the larger injector's "pulse width"(open time), to the point that it would probably set a "rich" code.

You could use a non-flex PCM and change to regular injectors, but you couldn't run E85.

PCM also needs to match transmission, if you have an auto(5R44E) then you need a PCM that can control the transmission.
If you have a manual trans then a PCM for an automatic would have the CEL on all the time because trans connections are missing.
If you put a manual trans PCM in an automatic then no TCC lockup or proper shifting.

Yes by all means pop the top on the PCM, it is out of warranty

The transistors(drivers) used for the coil pack get very very hot and can fail.
If you are old enough to remember "points" in a distributor, these transistors replaced what the points did, and points burned out regularly and had to be changed, which is why electronic ignitions are used now, they do last longer, usually the life of the vehicle, but not always

Only found this one picture of the inside of EEC-V, and it is from UK, so...: http://www.madinventions.co.uk/mojo/Images/ecu.JPG
Not sure Ford released schematics for EEC-V PCMs