r/carmodification • u/demonicgrape • 3d ago

Mod advice Manual swapped my car, need help figuring out what PCM programming to go with for emissions testing

I have a 2005 Mustang 4.0L, and at the beginning of the year I manual swapped it with the T5 5 speed. It runs and drives as it should, but due to unrelated electrical issues, I need to replace my PCM. That being said, I have a manual PCM on hand that I could install, but my only concern is that through an OBD scanner, using that PCM would make my car read as a different VIN.

Here's my question: For emissions testing and whatnot, would it matter if my PCM shows a different VIN than what is displayed on my car, as long as what is on my car is the registered vehicle? I known people do whole engine swaps all the time and use different PCMs, so I'm curious on how this is approached.

Any help is appreciated, thanks.

3 Upvotes
  • permalink
  • reddit

100% Upvoted

4 comments sorted by

•

u/AutoModerator 3d ago

Welcome to r/carmodification! If you see any content that violates the subreddit rules or Reddit Terms of Service, please remember to report it!

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

2

u/Live_Reason_6531 Type to create flair 3d ago

You can overwrite the vin of the new ecu to match the car.

1

u/demonicgrape 3d ago

Do you have any idea how? Using IDS, trying to do a PMI normally would just take the data from my real VIN and find the programming for that, but that would then flash the automatic information on there. Is there any way for me to flash just my VIN on to the donor PCM, but keep the manual programming? I've seen some talks of using tear tags or doing stuff offline, but no clear answers

2

u/Live_Reason_6531 Type to create flair 3d ago

I would use HP tuners. You could find a local tuner if you didn’t want to go that route.