Tuning ECM Without Unlocking TCM
 

I reached out to HP Tuners about this but haven't gotten a response. Can I tune my ECM without unlocking my TCM? I have 2018 A8 and know the TCM is locked, but to my understanding the ECM is unlocked. Installed a DSX Flex fuel sensor the other night and am looking at different tuning options, would rather not have to ship out / buy a new TCM if possible. Thanks!

Pretty sure the ECM is also locked on your '18.

You can tune your PCM only, you do not have to tune the TCM. You do not need to sent the PCM in for unlocking. When you decide to tune your TCM, it will need to be unlocked, or you can buy an unlocked unit from HPT. You will still have to buy credits for your TCM, even after unlocking to tune it.

This post is accurate. To add to it just a little, your ECM will cost four credits to tune. If you decide to tune the TCM, you'll need it unlocked ($200) on top of four credits for that module as well.

Thanks for the replies. I'm looking to get into tuning so I will start with the ECM. Good to know I dont have to send it in for unlocking as well.

How does one unlock the TCM? I have HPT and custom tunes, but my TCM overrides the STAB and reduces timing when I hit the gas at the drag strip. Cant get below 1.7 60', no matter what I try.

You have to contact HP Tuners and either send your TCM into them to have it unlocked and then shipped back to you or you can buy a new unlocked TCM from them.

As said, once you get the TCM back you will need to purchase 4 - credits ($50 each, $200 total for the TCM) to be able to tune the TCM.

Ok. I have 2 credits left.