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Purchased a 2017 GT & found it was tuned.

749 Views 7 Replies 3 Participants Last post by  JBert
I recently bought a 2017 mustang gt and it had a mystery tune didn’t find out about it until I went to get new tunes, the tuning company told me I’d need to reflash it back to stock for them to make the new tunes so I took it to a ford dealership and they told me that reflashing could lock my pcm and told me if it did it would be 900 to replace it. Any suggestions on what to do because I wasn’t sure if they were just feeding me bull do I have to spend that just too get new tunes?
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This is a common problem -- buying a used car with a "mystery tune" and without the tuner device. Unfortunately this puts you in a difficult situation . . .

I assume you did not get the tuner device with the car. If you did get the tuner device with the car, then the factory tune should be on the tuner and you can download it from there.

However, if the car is modified, with modifications that REQUIRE a tune to run right, then it will not run right without the tune. The most common example is an aftermarket "cold air intake" where the mass air flow metering section is larger than stock, which requires a tune to "recalibrate" the mass air flow calculations, or the car will run lean.

So, first you need to find out if the car has any modifications that require a tune.

If it does not have any mods that require a tune, you can have it reflashed back to stock by a Ford dealer. I had this done in ~2011 (because I was in this situation) and they charged me about $150, if I remember correctly.

Why do you feel that you must go back to stock tune?

... took it to a ford dealership and they told me that reflashing could lock my pcm and told me if it did it would be 900 to replace it. ...
I suppose that is possible, hopefully they were just warning you "just in case" .... it worked with no problem on my 2010 but I don't know if there are new issues in the later models that might cause a problem .... how much did they quote you for the factory tune reflash, assuming it did NOT lock the PCM?
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That's just fear mongering nonsense from the dealer. ...
... or maybe, looking at it in a more positive light, "an overabundance of caution" aka CYA ???

maybe talk to another dealer, if there is another one not too far away ... and it seems that smaller dealers can be more straightforward on this stuff, sometimes if you're lucky ;)
I paid $150 to reflash mine back in 2011, if I remember correctly ... yeah $240 is a bit high

it's hard to tell if they were setting you up with the "reflashing might lock the PCM" thing or just giving you fair warning of what "might" happen

is there another dealer you can try? I'm thinking there must be more than one in the Tucson area
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