Dealer can't flash 2018 Mustang PCM back to stock. What are my options?

[WesDuenkel]

I just purchased a 2018 Mustang GT, and am having a major problem that I hope the hive here can help. I suspected the PCM was tuned, so I tried to read the tune file in the car with my MPVI2, and got "Validate checksum failed. Controller TC-298. Definition failed to load. You will be unable to edit this file."

Sent the files to HPt as directed (files attached for reference), and they said "Unfortunately, this PCM has been previously tuned and the operating system modified from stock. We will not be supporting this file. A Ford dealer tool might be able to fix the PCM, then just reread with our software. When an operating system has been modified from stock it can cause multiple issues anything from checksum-related issues to fried ECMs during the flash process."

I took it to a local shop with the Ford VCM2 device with IDS software, and operated by an experienced Ford tech. He was unable to reflash the PCM. He's reflashed "probably 40 vehicles back to stock, and never had this problem." Great. He described the problem as, "There's some kind of high-level bock in place that's different than a typical tune. Maybe it's a Roush or FPP tune that has a blocker or something."

So, I'm stuck. What are my options? Thanks in advance for any advice!

[K44]

99% of the time this is a Lund tune. If they kept a record they can send you a stock tune.

Only other option is a new PCM.

[WesDuenkel]

Noted with thanks. I'll email Lund and see if they can help.

[TheMechanic]

Other option is to have the PCM replaced. Looks like FS1 has them pre-programmed for about $600

[veeefour]

Very easy to do, you can send it to me i will bring it back to stock no matter whats in there

[Bill@HPTuners]

yeah its a scrambled operating system, could be one of many tuners. Doesn't appear to be one of our scrambles though.

[WesDuenkel]

yeah its a scrambled operating system, could be one of many tuners. Doesn't appear to be one of our scrambles though.

Noted. Thanks for the help! I'm just trying to solve this problem, and coming up short. I'm afraid if I send the PCM off to be "reflashed back to stock" they're going to tell me the same thing. But, I'm clearly not knowledgable enough to understand the capabilities (and limitations) of these processes.

[RobCat030]

I'm going to PM you. Even in the worst of cases (say, the flash is legitimately corrupted), you can usually flash in recovery mode with IDS. If UDS was modified you would likely would not have been able to get a read at all.

[WesDuenkel]

I'm going to PM you. Even in the worst of cases (say, the flash is legitimately corrupted), you can usually flash in recovery mode with IDS. If UDS was modified you would likely would not have been able to get a read at all.

UPDATE: Holy cow, I was able to track down the previous owner (never thought that would happen), and he indeed used a Lund nGuage. He's sending the nGuage to me so I can HOPEFULLY use it to flash back to stock and all will be solved!

Thanks for all the help. I'll follow up if (when?) I have more issues.

[K44]

Great news. I hate tuners that scramble the OS. Locking should be good enough.

[Bill88stang]

Let me know if you want to sell that ngauge for a few bucks it would be nice to be able to have one just to view data while driving

[dnun93]

Do not send your pcm to veefour he got me for 350 $. I would highly suggest not doing business with him. Multiple people can back me up on this forum. Just trying to save you the hassle of having to deal with that foolishness. I can assure you you?d likely never see your pcm again and be out of your money too.

[WesDuenkel]

Unbelievably, I was able to track down the previous owner, and he had the nGuage with the factory calibration. I was able to return it to stock and all is well!!! Thanks for the leads, everyone.

[Seishuku]

Good stuff! I do wish people that install canned tunes like that, would send the paired tuning device with the car when trading in... Then again, who's to say that the deal would then loose/throw away the device...

Edit:
Well, not exactly a canned tune, but a paired device still.

[veeefour]

Do not send your pcm to veefour he got me for 350 $. I would highly suggest not doing business with him. Multiple people can back me up on this forum. Just trying to save you the hassle of having to deal with that foolishness. I can assure you you?d likely never see your pcm again and be out of your money too.

You again...stop selling lies. Only you had a problem with a good basic n/a tune because you wanted to take a tune+refund at the same time.
You've been doing ths for many months, gathering the tunes and later selling lies how it's not working for you...

Paypal said no to you and even blocked you PP account and ruled the case on my favor. Now you sad and sour and trolling on forums...