Having little trouble accessing site, trying again.

It would be 2 or 3 digit one or the other, would not change based on what was used to read/access them IE; sounds like might be user error but would need know exactly how the test was run.

Counting flashes for example, easy to miss count get it wrong different result every time.

You didn't state which tests the codes are a result of, tends be important.

527 would be for a car per say if correctly read and you could simply disregard that one if it is, least for the time being.

Park - Neutral Position / Neutral Drive Switch doesn't have one on yours for example, be an unused pin for example so its throwing the code.

556 is for the fuel pump relay circuit, did you remove and reinstall it just to verify it makes solid connection IE; its not all corroded at its pins.

That year gets all power from several fuseable links on battery side of fender mounted relay, might be an issue there. Be sure none are corroded falling apart and are clean tight.

Do both those code reappear after clearing codes running self test and or drive cycle? Are they the only codes you do get?

Should attempt read codes yourself, see what you come up with if anything.

If you haven't clear the codes and start fresh.

Fuel Injection Technical Library » How To Run a Self-Test

 

I think the mechanic that got the 2 number codes didn't really know how to perform the test, but the others that did all got 3 number codes. I have no way to read codes....is there anything on the market that doesn't cost "much" and works well. Do parts stores ever rent code readers? Once I install the right ECU for the truck I'll start over and disregard everything that has been done so far......I don't trust codes from an ECU that doesn't belong in the truck!

 

.is there anything on the market that doesn't cost "much" and works well.

Link I posted show how to do it for free requiring nothing more then say a paper clip.

Look for a innova 3145, bought mine on ebay for 20 bucks. Was "used" but like brand new and included the manual for it.

Counting "flashes" gets it done but the reader is easier.

 

Code 556 is very common on dual tank trucks and it's a complete red herring and can be ignored. Code 527 is a wiring problem, the computer is not getting a constant 12v on pin 1 which could be from a corroded or broken wire on the EEC relay.
Overall I think you're barking up the wrong tree with this and will see the exact same problem with the "correct" computer. For the most part the computer pinout doesn't change from year to year for any specific powertrain combo so there is a lot of interchangability between them, and you would immediately see codes for specific sensors if there was a pinout mismatch.

Maybe sombody can lookup the FOAF-14A459-AA EEC and tell us what that is for, if it's for a vehicle other than a truck then you have a case for wanting to change it.. though the fact that the engine runs at all demonstrates just how similar these thing are.

 

I might see the same problem with the correct computer, but at the least I want to have the right computer. I've heard from a lot of people that having the wrong computer can cause issues and wrong code readings, so to properly diagnose any issues, I need to start with having the right ECU. I had people look up the FOAF ECU and after doing my own research, it was determined that it shows up in Broncos and Mustangs. Thanks for the feedback....this is a great forum!

 

DTC 527 = Neutral Drive Switch (NDS) circuit open; A/C ON (Manual). Nothing to do with the Keep Alive Memory (KAM), like Paul and others noted before. I have not looked too far into the PCM compatibility, but the F-series and Broncos share the same PCM Calibration codes.

 

What's the catch code on the computer you have now? It will be on the connector in large letters.

 

It reads: 586ECM
9223 1012
E9AF-14A624-AA (GTE)

 

So you're saying there is no catch code, like the examples in my post?

"E9AF-14A624-AA" is just a generic Ford engineering number for the computer case/connector itself. Re-manufactured computers typically have it.

 

E9AF-14A624-AA would not fit any truck, I think that number is for a car.

The truck numbers have a "T" in them and the part number would have a "Z" in it.
The "F" is the engineering number.

As I posted above:
The number on the unit is:
F0TF 12A650-BB and is the engineering number for the computer itself.

Ford Part number is this and is not found on the computer:
F0TZ 12A650-BB

 

I have a 87 F150 with a 302. It is a dual tank. The front tank never worked so I have allways just ran from the rear tank to keep from messing with it. Recently I have gas shooting from the rear gas cap. Like a pressure build up. The front tank is deffiantly empty. Anyone have any ideal what could be causing this to happen. Also tried running without the gas cap on either tank and is still building up pressure.