madmatt9471

I agree - that makes me think of Edelbrock's Supercharger and how they have a canned tune that is CARB E.O. approved that comes with their kit - they too should be good to go -

Look up the EO number and read the PDF on both A&A and Edelbrock if you haven't already, it's pretty enlightening -

Thanks,Matt

madmatt9471

Someone could always go this route if they had some serious nuggets -

https://dna-octanemotorsports.com/cvn-correction/

Thanks,Matt

madmatt9471

Okay fella's here is an update -

Everything is back to stock - I had a busy week and I am still going to try and get the Vette over to the SMOG shop to check the CVN Checksum(s) - from HP Tuners that I dropped in the Vette, my "Stock Tune", saved on my laptop with HP Tuners, it is download and it has all the values in there - but for all of our sakes let's hope that it is good to go and this will be an answer to part of the Puzzle

Will we be able to use our Stock saved tunes saved on HP Tuners or not? - Y/N

Thanks,Matt

turbrorx7

Very interesting, how much is it?

AQWIKZ

I have order another ECU with the factory tune my my car. just will have to swap ECU and do the same thing and have it checked to make sure everything is okay. I am good for two years right know. just want to make sure I have everything lined up before hand. The ECU is refurbished and will have my Vin number assigned. Only will have to do a key relearn procedure. The cost was 150.00 shipped from Flagship One Inc.

Jfryjfry

Please keep us posted here on what this takes. I have spent a long time researching exactly what it would take to do this and it is surprisingly hard to find much info, and none of it is definitive. What do you need to get the new ecm to work with everything? More than a tech 2? Do you even need that?

I’ve read conflicting reports, but no firsthand info.

AQWIKZ

I will keep all updated. No Tech 2 is need from what I was told. just remove original and plug in the new one, make sure the battery is full charged and do the key re-learn for security of the car and that is it. hopefully that is all.

vinceg

That would look like the batt has been disconnected. Then you would need to go do all the cold starts warm ups cycles for drives. At that point you would throw codes. If you had a cam

madmatt9471

Okay - so I just finished at the SMOG shop to see if my "Stock Saved Tune in HP Tuners" would pass SMOG - I had the full check done with it just short of it being sent to Sacramento annnnnnnnd.............

All is good, it passes with NO ISSUES, no CVN Checksum numbers missing or HP Tuner thumbprint - I will not have to go to the GM Dealership and have them re-flash the ECU (PCM) with the stock tune. Of course this is "My" stock tune that I saved on HP Tuners in a file and named and even the name file did not affect the results

To understand the CVN Checksum(s) I ran my VIN here: https://tis2web.service.gm.com/tis2webyou can see your operating system here and checksums (CVN) - it's really interesting and starts to make sense of what they are looking for. Once you see it and then understand that as soon as you make a change it changes the CVN number in the said system. (Timing, airmass, transmission, rear gear, etc.)

This is good news for those of us who have our "Stock" file tunes saved, knowing that we can re-download them from HP Tuners or EFI Live or another programmer that might hold your stock tune -

It's also to note that from some of the research that I did I found reference to our E38 ECM's and they do not have "Bit Counters" in them, meaning that some vehicles have counters in them that count every time you access and rewrite the ECU (PCM) - counting, if you will, till you reach the maximum allowed times and then either having to have it rewritten by the dealer or getting a whole new ECU (PCM) - please don't hold me to this as I do not have conclusive evidence about our E38 ECU's, however, it's a bright side again in this saga!

I hope this helps! I know that it helped me, it helped save me an additional $425.00 to have GM re-flash my ECU

Thanks,Matt

madmatt9471

Got this going on here in the C6 General Section: very interesting

https://www.corvetteforum.com/forums...-software.html

Also these two other threads in the C6 SCAN and TUNE section for our two local members:

https://www.corvetteforum.com/forums...mog-check.html
https://www.corvetteforum.com/forums...smog-test.html

Want to add this thread here too as it is pertinent: A&A Smog Legal Kit. Komifornia Now Scanning Tunes. Questions?

https://www.corvetteforum.com/forums...questions.html

Thanks,Matt

heggsc5

Just read through these threads, thanks for keeping us updated!

madmatt9471

Hey man you are welcome as is everyone else - I will continue to do whatever I can.

Thanks,Matt

AUandAG

I swapped my street tuned pcm with a refurbished unit programmed with my vin ($115). I verified that the cvn's now match the oem tune so passing smog shouldn't be an issue. After install, I did the key/security relearn. The engine started right up and immediately threw the "p1336 Crankshaft Position System Variation Not Learned" code. Easy 2 minute fix with the tech2 clone I purchased anticipating that it would be needed to clear that code.

madmatt9471

It looks like you will have to contact them for the price - you would have to send them your tune file via email and then send them the stock tune file and they will create for you the corrected CVN over the modified tune -

They are out of the country so you will either have to contact them by email or by phone (listed at the top of the page)

Thanks,Matt

madmatt9471

Glad you got this worked out and you had the Tech 2 clone to solve the relearn issue - I am also glad that this thread is still going as it will continue to help many -

Thanks,Matt

Jfryjfry

where did you get the ecm from?

and can you do a quick summary of how to do the relearn? I’ve hardly touched my tech 2

AUandAG

I purchased the PCM/ECU from Ares Technologies.

This is how to do it for a C5 on my tool. I assume it's the same for a real Tech2.

On the tool, select GM, manual selection, model year, passenger car, powertrain, (G) 5.7L V8 LS1, Y (body), 4 speed automatic or manual, powertrain control module, special functions, crankshaft pos.variation learn

An information screen indicates the RPM value for fuel cut-off: v8 = 4000 RPM

ok, block drive wheels, set parking brake, cycle ignition from off to on

Press and hold brake pedal, start and idle engine, turn off A/C, place in park or neutral

Rev engine up to 4,000 RPM, release gas when you feel fuel cut-off

As I recall, the tool will then indicate the crank position was learned and you are DONE.

P.S. After one trip of about 30 miles, all monitors were ready except evap so the C5 is ready to pass a smog test. (I read that the evap monitor will be ready after the fuel tank is below half-full.)

Hope this helps...

Jfryjfry

Awesome. Thanks so much!

IRVINEC6

I do not have my original stick tune, so does that mean I am out of luck?

madmatt9471

No it does not - because you can save or copy this tune, your current performance tune, in HP Tuners or if you do not have HP Tuners you can have your tuner save/copy it for you for a reinstall later etc.

Then go to the GM Dealer and have your stock tune flashed into the ECU - then if you decide to have the performance tune flashed back in, the tuner or you yourself 9if you own HP Tuners) can reinstall it in the ECU (PCM), however before you do that you will copy your new "Stock" file and download it to your computer and save it in a HP Tuners file (if you own the program or if you do not own the HP Tuner program you will have your tuner do that for you)

If you do not own HP Tuners, a tuner can send you a copy of your performance tune and stock tune as a file(s) in an email, you can keep that in your email or in an email folder for safe keeping, and you will be able to forward those tunes to any tuner when needed, they would then be able to use it on your Vette.

I hope that makes sense - lol

Thanks,Matt