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· Registered
7 Posts
Discussion Starter · #1 ·
Hey guys,

I'm working on a 2.0 Ecoboost swap. I have a few questions regarding doing a swap specific to the wiring harness, ECU, ignition system, and keys.

Is there any concerns about using a engine from one totaled car and a ECU from another?

Are the ECU's coded to work only with the key's coded to work with that car?

Lastly is there anything I should be aware of doing an engine swap specific to the wiring, ignition, and ECU?

Thanks for reading?

The link below shows car I'm swapping the engine into below.

· Registered
101 Posts
I have the same question. I got a low mi 2016 motor for my 2014 and it came with the ECU. Problem is the harness from the 2016 is different from the 2014. Or rather
the ECU connectors (there are 2), are different. I have had three dealers tell me they use my old ECU. How? It’s not programmed to the newer engine, which I’ve driven a few newer ST’s and they run better, seem to have much more linear power band too. To me it’s important to use the ECU from the new (used engine) .


· Super Moderator
2017 Kona Blue ST1
5,798 Posts
Yes, there's wiring changes from year to year. For the money that you will spend to replace harness and making the other necessary changes would be better spent on an AP3 and a decent tune.

The factory programming really isn't worth breaking the bank for. If you're concerned about keeping the vehicle stock (or as close to stock as possible) then my suggestion still holds. There are several tuners that will help you achieve whatever your goals are.

Just throwing it out there.

Stay safe and have a great 4th!

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