Alright, So I've been trying to find the answer to this question but cant seem to get one. I'm looking to swap out my blown 2010 XF 4.2 Engine with a Running 2010 Supercharged 4.2 Engine. I know this isn't the easiest job, however I feel like its more then capable of being done. I also understand ill need maybe an additional water pump and some electrical mods, but my main question is regarding the Engine Bay Wiring Harness. I know ill need to replace mine with the SC ones. However; I need to know A) are they compatible? I don't see why they wouldn't fit but of course need to be sure. B) would it have to be the specific year? ie 2010 or will 09-12 SC wiring work too since the model is the same. and C) if my Base 2010 can be wired up with the SC Harness, What else will I need to replace? ECU? please remember the only thing I'm really changing is the Supercharged option. Still 4.2

 

You will need to get the supercharged ECU as that will have the extra pins for the extra functions of the supercharged engine. Some of the other modules (say TCM) may also need to have their programming updated to respond accordingly to the supercharged feature.

As for what years, I think you have a bit of a unicorn as I believe the XF switched over to the 5.0L engine in 2011. So, you pretty much have only 09-10 to look at.

 

I also think you'd need the SC PCM (aka ECM aka ECU) but it will expect the trans and its software to be the SC variant, which may or may not matter.

Expect grief, sadly....

 

Yes with the difficulty of doing that swap and with the low value of the car you would be far ahead to sell what you have and buy a SC version if that's what you want.
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