Replace PCM for a tune?

[RR_S550GT]

Some time back I posted the mild saga of the error codes and affiliated check-engine light (link).

TLR - I unknowingly bought the car with a tune of unknown origin, it threw a code on the way home in November. Drove great then and now. Initial dealer indicated they thought the trans was swapped since the code is associated with a transmission speed sensor that DNE on the revised MT-82 in the 2018+. Left that dealer with the car around the holiday's.

Finally, after mostly storing the car over the winter, I decided to take it back to another dealer to work through the issue. It's been a day and a half, and the Service Manager is suggesting that they "can't read the computer" and is now working on a price for a PCM replacement. I find this somewhat hard to believe... the the firmware simply can't be updated, but the Service Manager only said, "it's not that easy."

Would anyone have any insight? Is the above accurate and sane? Thanks for any input, much appreciated.

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[Bluelightning]

Some tuners encrypt the entire PCM, some just the tune, so depending on who the tune was from.....

 

[RR_S550GT]

Some tuners encrypt the entire PCM, some just the tune, so depending on who the tune was from.....

Thank you, I hadn't realized that. Given the unknown origins, this should be fun.

 

[Jordan @ Lethal]

It's tough to say what could be causing that problem. You certainly can't rule out a swapped trans but there should be some evidence to accompany it. Ultimately, you're probably going to want/need to get it revised tuning.

 

[Bluelightning]

It's tough to say what could be causing that problem. You certainly can't rule out a swapped trans but there should be some evidence to accompany it. Ultimately, you're probably going to want/need to get it revised tuning.

The problem is he can't get it retuned as the PCM has been locked so that Ford can't even read it or flash it back to stock with IDS. Car came with an aftermarket tune on it, but no device or way to flash it back to stock so it can be diagnose from the dealer... So, yeah he needs a retune, but it's not that simple...

 

[RR_S550GT]

The problem is he can't get it retuned as the PCM has been locked so that Ford can't even read it or flash it back to stock with IDS. Car came with an aftermarket tune on it, but no device or way to flash it back to stock so it can be diagnose from the dealer... So, yeah he needs a retune, but it's not that simple...

Appreciate it, so perhaps the PCM replacement is the appropriate path? Anyone have a sense on reasonable cost?

 

[WildHorse]

Appreciate it, so perhaps the PCM replacement is the appropriate path? Anyone have a sense on reasonable cost?

Ask LUND why TF they feel the need to encrypt the whole PCM with no way to return it to stock.

 

[Brazos609]

You certainly can't rule out a swapped trans but there should be some evidence to accompany it.

Simply running the VIN will tell you or the dealer the original configuration of the car, manual or automatic.

 

[RR_S550GT]

Simply running the VIN will tell you or the dealer the original configuration of the car, manual or automatic.

Can confirm that it has a manual and is supposed to... my theory has been that the code for the speed sensor is related to the tune, but earlier versions of MT82 did have this sensor, which they no longer do on 2018+.

For sure this is just my logic and not fully validated.

 

[MKL_DS]

If the dealer was crafty, they would figure out how to flash it back to as built status, however, if there are mods on the car that require a tune, you open another can of worms there.
Get it in front of a competent tuner who understands the current situation and the problem should be easily solved.

 

[K4fxd]

It's a Lund tune you have 2 options. Buy a tuning device from Lund and have them send you a stock tune or have the dealer install a new PCM.

 

[Jordan @ Lethal]

The problem is he can't get it retuned as the PCM has been locked so that Ford can't even read it or flash it back to stock with IDS. Car came with an aftermarket tune on it, but no device or way to flash it back to stock so it can be diagnose from the dealer... So, yeah he needs a retune, but it's not that simple...

Thanks a lot bluelightning for making that so clear. If you hadn't come along to to literally rewrite it all but but in a nasty manor, I doubt I'd ever have fathomed what this could possibly have been about. So, yeah... Leave your negative bs at the door. It's a forum. One for which I was just hopping in to join the conversation and see where it leads. Not sure why you feel the need to attack/lash out at someone in a forum who has said nothing ill-tempered in the first place to warrant such malice but it's in the worst taste.

 

[shogun32]

Would anyone have any insight?

quit taking it to dealers and find a Mustang specialist.

It seems the tune was provided by a lazy and sloppy outfit who didn't pay attention to the model year and differences therein. Or less likely someone put in a built MT82D5 or TR trans for a while, tuned it in that condition, and then swapped the MT82D4 back in to sell it and didn't finish undoing all the mods.

My money is on lazy/sloppy/irresponsible tuner.

 

[Bluelightning]

Thanks a lot bluelightning for making that so clear. If you hadn't come along to to literally rewrite it all but but in a nasty manor, I doubt I'd ever have fathomed what this could possibly have been about. So, yeah... Leave your negative bs at the door. It's a forum. One for which I was just hopping in to join the conversation and see where it leads. Not sure why you feel the need to attack/lash out at someone in a forum who has said nothing ill-tempered in the first place to warrant such malice but it's in the worst taste.

Nothing I said was with malice. You simply glossed over the part about the dealer not being able to access his PCM. You simply suggested that he needed to get a revised tune, which isn't possible without the original tune device or stock file that didn't come along with the used car he purchased. We all know that one of the companies that you work with encrypts the entire PCM, which is most likely causing the problem that he is having with the dealer suggesting that he needs a new PCM as they can't access it. If you would like to be helpful, maybe you could get with that tuner that you guys sell the products for and see if they can help the guy out.

 

[Jordan @ Lethal]

Nothing I said was with malice. You simply glossed over the part about the dealer not being able to access his PCM. You simply suggested that he needed to get a revised tune, which isn't possible without the original tune device or stock file that didn't come along with the used car he purchased. We all know that one of the companies that you work with encrypts the entire PCM, which is most likely causing the problem that he is having with the dealer suggesting that he needs a new PCM as they can't access it. If you would like to be helpful, maybe you could get with that tuner that you guys sell the products for and see if they can help the guy out.

Specifically, the dealer can re-flash the car back to stock no matter who has tuned it. I know this with certainty. The dealer not being able to read it doesn't mean they can't. In my initial statement that may seem like I glossed over that, I was incorporating that he likely needs to go ahead and start fresh with his car with new tuning from Lund or PBD or whoever. He doesn't need a new PCM unless it's become fried/damaged etc. I actually had spoken with PBD about this matter before writing what I wrote. No one here has yet made a phone call on the OP's behalf I imagine. Helpful is all I'm here for.

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