1997 4.6l ECU\PCM question

I was given a SOHC 2V 4.6 and 4R70W that came out of a 1997 Mustang GT. I was told there is nothing wrong with the engine or trans and they were pulled for a Coyote and Tremec swap. Everything is as pulled including engine wiring and accessories except for the AC. What I don't have is the ECU\PCM or the VIN from the car it came out of. Is there any way I can find out which ECU\PCM I need for the engine with what I do have? I haven't found anything by searching the web that backtracks from the engine number. It's a Romeo engine if that matters for the ECU.
 
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It might be better if you mentioned WHICH model year car you are planning on putting this in.

You don't have to have the original PCM or the VIN # from the original.

There isn't a marriage between a PCM and a specific individual motor.
 
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I haven't decided what to put it into yet but probably a 76 Montego or a sand rail. I would appreciate an explanation of there not being a marriage between PCM and a specific motor. I could go to any number of after market ECU's and wiring harnesses but was looking to keep the cost of this build down. Also I screwed up as this is a 96 motor, not a 97. The calibration code on the motor is 6A836AB.
 
I would appreciate an explanation of there not being a marriage between PCM and a specific motor.
The exact same "long block" 4.6 is found in a number of different Ford "applications". This is further evidenced by the large number of people that have taken a motor from Crown Vic's and put them (with some external modifications) into Mustangs.

I'm sure it's easy to see that the PCM in a Crown Vic is different from a Mustang. And different from a F150. As long as the motor is "trimmed" as the PCM is expecting the PCM will not know the difference. Note, by "trim" this means the entire motor package including electrical and car body support systems.

So you see that "technically" there is a long list of PCM model years from multiple "applications" that could work in a transplant situation. Your challenge is going to be to figure out which will make the most sense to adapt to your intended use.

Since your 1996 4.6 is:
  • non-PI
  • coil pack
  • return fuel system
  • Car style intake
If your intention is to re-use the 1996 Mustang GT wiring harness then this will restrict the PCM to a 1996-1997 Mustang GT. 1998 has a strange two speed fuel pump. 1999+ uses COP ignition. So that's out.

Consider going to car-part.com and search for a PCM from a 1996 Mustang GT with an automatic. Use the calibration that comes with the PCM.

If using a stock PCM instead of an aftermarket PCM it seems to me the challenge is going to be the sum total of the wiring needed to allow the PCM to do it's job. Remember the PCM is going to be looking for things like an EVAP purge system and EGR. ABS/traction control. Anti-theft.

Systems in the car not really associated with the Motor. Perhaps a lot of "modification" in your future. Some of these issues are why some will choose a stand along after market PCM for such a transplant project.
 
wmburns, Fair enough. I wasn't sure what you were saying and just wanted to verify that you weren't saying any PCM from a 4.6 would work with any 4.6 motor. Your identifying a PCM being more than a ECU\EMS is why I'm trying to track down the right calibration for the engine. You could have added to your list of potential problems can be expanded with the less obvious problems of changes to the SCP and the CAN\BUS systems and the advances in multiplexed system operating frequency (speed).

I looked into car-part.com and I see what is listed as a 1996 Mustang PCM with a picture of the vehicle it's coming out of and it's an F150 and the calibrations aren't listed. This is where I get confused and why I want to try and track down the exact PCM that came in the car. Will a PCM from an F150 work? The intake runner length is different for the truck but does that mean the programmed parameters won't work? I don't know and that's the kind of information that isn't readily available that spooks me from blindly trying PCM's. Unfortunately there are about 40 different calibrations for the 96 Mustang and recalibrating with a know calibration is more often unsuccessful than successful. I've been given a lot of different reasons for this happening ranging from age of the PCM to changes in the Windows IDS operating system. The OS is the reason a lot of the Haltech Programs use DOS instead of windows.

Looks like the motor is going into the rail as a project. As a last resort I can revert to a simple Megasquirt EMS. Your last sentences point out what's ahead.