Engine and Transmission swap (ECU Swap)

2001 FORD MUSTANG
168,000 MILES • 3.8L • 6 CYL • 2WD • MANUAL
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ANDY DUCHESNE
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Hi,
I just purchased the car listed above that has had a low km 3.8l swap done and a transmission swap (went from Automatic to Standard), i am still using the original ECU, should I be putting in the ECU from the donor car? Or should I be keeping the original ECU I have and reprogramming it?

I don't have a key for the other ECU.

Thanks in advance.
Jun 9, 2022 at 2:57 PM
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KASEKENNY
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Just to be clear, is this vehicle running with any codes? I get the impression that it is running but you are just wondering if you should put the ECM from the vehicle that the engine and transmission came out of?

If this is the case, you do not need to swap this if the vehicle is running.

I imagine you have a couple codes if you went from an auto to manual transmission because the manual has less sensors. So, let's check the codes.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

If there are no codes or even if there are, you do not have to change the ECM if the vehicle is running.

Basically, if the engine was a 3.8L then the replacement 3.8L will be the same. The engine is not VIN specific on this vehicle.

Let me know if I am not understanding it properly.
Jun 10, 2022 at 7:44 PM
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ANDY DUCHESNE
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Yes, you have it 100% correct. I just need to program out (I think) the Manual transmission items that I no longer have. I think lol, new to the computer car stuff, I am a computer tech but not when it comes to cars.

Thank you Kenny!
Jun 11, 2022 at 8:02 AM
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KASEKENNY
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Haha. Yeah, then your manual transmission will operate as it clearly doesn't need the sensors the auto does.

There are a number of programmers out there that you can use. Basically, it just tells the PCM to ignore the sensors that it no longer needs, and the check engine light turns off (if it is on).
Jun 11, 2022 at 10:56 AM