[bereic]

H,

2 friends of mine got his car tuned some times ago.
Now they want to delete/deactivate the AFM and the 3rd Gear throttle (it comes from factory on export cars, the 3rd Gear has nearly no response between 30mph - 37mph).

Now, the company who did the tune doesn't exist anymore and they aren't able to ask him to do it.
As I own a HPT they asked me if I could do it for them.

My question is now, can I just simply read his file and adjust the calibration on AFM and 3rd Gear and rewrite it or will it harm the initial tune somehow?

Sorry for the dumb question. But I am not yet so familiar with HPT as I bought it for my cars, where they are all stock and just needed it for AFM and 3rg Gear deactivation.

Thank you very much for your help.

[arpad_m]

The tune may be locked, in which case you won't be able to adjust it. If it isn't (hopefully), and of course assuming the original tune was created with HPTuners and not a different device, you should be good to go, but you need to buy vehicle credits from HPTuners to be able to actually write a new tune into the car.

This is the first time I'm hearing about this "3rd gear throttle", by the way, none of the European SS reviews I watched on youtube mentioned it, interesting.

[bereic]

Thank you.

He got a stock file and a Tune file from his Tuner. He is going to send me those.
So, if it is not done with HP Tuners but a different device, you think I wont be able to adjust it?
How would I see if it is locked?
Yes I know he would pay the credits.

It's a well known issue for the european ones. This was done to meet the regulation on C02 and the noise on the MT and AT. On the AT you only feel it when shifting manually. It's a horrible feeling pushing the pedal to the metal and nothing happens..
See attached screenshot

[arpad_m]

Originally Posted by bereic

It's a well known issue for the european ones. This was done to meet the regulation on C02 and the noise on the MT and AT. On the AT you only feel it when shifting manually. It's a horrible feeling pushing the pedal to the metal and nothing happens..
See attached screenshot

Wow, these parameters are not present in any of the US model tune files I have seen. Learned something today as well, many thanks

Originally Posted by bereic

How would I see if it is locked?
Yes I know he would pay the credits.

It's a well known issue for the european ones. This was done to meet the regulation on C02 and the noise on the MT and AT. On the AT you only feel it when shifting manually. It's a horrible feeling pushing the pedal to the metal and nothing happens..
See attached screenshot

Regarding locked tunes, read this at HP Tuners' website: http://www.hptuners.com/help/VCM-Edi...tuning_ids.htm. It would be a hostile and somewhat unlikely move, just something to be aware of and check before buying anything.

Originally Posted by bereic

He got a stock file and a Tune file from his Tuner. He is going to send me those.
So, if it is not done with HP Tuners but a different device, you think I wont be able to adjust it?

What I meant here was that EFI or Diablo have completely different tune file formats, I don't think the software HP Tuners provides ("VCM Suite") is able to work with non-native files, so it's best to make sure the previous tuner used HPT as well.

[bereic]

Wow, these parameters are not present in any of the US model tune files I have seen.

Yeah european regulation...

Regarding locked tunes, read this at HP Tuners' website: http://www.hptuners.com/help/VCM-Edi...tuning_ids.htm.

Thank you. Will check as soon as i get them.

What I meant here was that EFI or Diablo have completely different tune file formats, I don't think the software HP Tuners provides ("VCM Suite") is able to work with non-native files, so it's best to make sure the previous tuner used HPT as well.

Just for my understanding as I was doing tunes for BMW in the past.
BMW calibration where done just with parameter changes. So the changes were done in the Software on a laptop and then send to the car where the calibration have been written into the car. But then there were also complete new flashes (Alpina for example) where you need to flash the ECU with a new software and afterwards adjust the parameters/calibration to your specific car.

So, on the GM cars the "Tunes" are these only parameter changes done in the ECU with HPT or other Diablo and so on.. or are there also complete flashes with other software on the ECU? Sorry for the maybe dumb question.. but still learning.
So if it is only parameter changes... should I then not be able to just read the tune from the ECU, change my parameters and rewrite it? Will this not keep the initial tune ?

Thank you

[arpad_m]

Originally Posted by bereic

Just for my understanding as I was doing tunes for BMW in the past.
BMW calibration where done just with parameter changes. So the changes were done in the Software on a laptop and then send to the car where the calibration have been written into the car. But then there were also complete new flashes (Alpina for example) where you need to flash the ECU with a new software and afterwards adjust the parameters/calibration to your specific car.

So, on the GM cars the "Tunes" are these only parameter changes done in the ECU with HPT or other Diablo and so on.. or are there also complete flashes with other software on the ECU? Sorry for the maybe dumb question.. but still learning.
So if it is only parameter changes... should I then not be able to just read the tune from the ECU, change my parameters and rewrite it? Will this not keep the initial tune ?

Thank you

Ah, I see, I see. An assumption I made was that you would be supplied the saved tune file by the previous tuner, but now I see that isn't necessarily the case.

The scenario you described will work when only the engine control module (ECM) or perhaps the fuel system control module (FSCM) or, for newer model years, chassis control module (CCM) settings needs to be altered. If that is the case, yes, you can read out whatever is currently in the vehicle, tweak it with HPTuners, then write back the changed tune (the official term for which is "calibration") and iterate as many times as you want.

I think this may be just fine for you, as most AFM/DOD settings are in the engine control module, but the tuning of the (automatic) transmission and the engine are very intertwined on this platform.

Now, unfortunately, if you have an automatic transmission, which I also assumed since you asked about AFM, the tune for GM's transmission control module (TCM) cannot be read out of the vehicle, it can only be written. When you try to read the transmission, you will get a default/stock calibration instead of what's currently in the car's TCM (because GM...).

The way tuners handle this problem is that they take this stock transmission tune, change everything they want, then save the result and give it to their customers, often creating a combo tune file that contains the tune for every relevant module—and that is why I asked about the format of the previous tune. If you want to use HPTuners, you can only continue tuning where the tuner left off from a saved HPTuners tune file, not something else.

Now, is it absolutely necessary to tune the transmission as well? Maybe not, but with the 8L90 it's almost mandatory, if only because a transmission tune can prevent or eliminate the infamous A8 shudder.


Hope all of this makes sense. There are several totally arbitrary, nonsensical limitations one has to put up with, courtesy GM.

[bereic]

Hi arpad_m,

thx for your explanation. But maybe I do not fully understand now what am i able.

Ah, I see, I see. An assumption I made was that you would be supplied the saved tune file by the previous tuner, but now I see that isn't necessarily the case.

I got them now and those are "xyz....cmd.dat" files. So not .hpt.
I guess no chance to read them without knowing the Tool/Software used?

The scenario you described will work when only the engine control module (ECM) or perhaps the fuel system control module (FSCM) or, for newer model years, chassis control module (CCM) settings needs to be altered. If that is the case, yes, you can read out whatever is currently in the vehicle, tweak it with HPTuners, then write back the changed tune (the official term for which is "calibration") and iterate as many times as you want.

I think this may be just fine for you, as most AFM/DOD settings are in the engine control module, but the tuning of the (automatic) transmission and the engine are very intertwined on this platform.

The changes to be done are in the ECM (E92 ECM). So you are saying I can read the current loaded calibration from the ECM... change the parameters for AFM and the 3rd Gear and upload it again, without harming the Tune he has on it?

Now, unfortunately, if you have an automatic transmission, which I also assumed since you asked about AFM, the tune for GM's transmission control module (TCM) cannot be read out of the vehicle, it can only be written. When you try to read the transmission, you will get a default/stock calibration instead of what's currently in the car's TCM (because GM...).

No need to touch the TCM as AFM and 3rd Gear are in the ECM.

The way tuners handle this problem is that they take this stock transmission tune, change everything they want, then save the result and give it to their customers, often creating a combo tune file that contains the tune for every relevant module—and that is why I asked about the format of the previous tune. If you want to use HPTuners, you can only continue tuning where the tuner left off from a saved HPTuners tune file, not something else.

With this you are confusing me now.. :-).
I do not want to touch the tune on VMAX and TQ.. only the AFM and 3rd Gear.

[arpad_m]

Originally Posted by bereic

I got them now and those are "xyz....cmd.dat" files. So not .hpt.
I guess no chance to read them without knowing the Tool/Software used?

Unlikely.

You can ask in the HPTuners forum if some tool exists to import tunes from competitors' software, but I don't know of such a tool.

Originally Posted by bereic

The changes to be done are in the ECM (E92 ECM). So you are saying I can read the current loaded calibration from the ECM... change the parameters for AFM and the 3rd Gear and upload it again, without harming the Tune he has on it?

Yes. You will need to buy 4 credits from HP Tuners to be allowed to tune your ECM.

Just for the record, this means you will not touch the transmission (or the fuel system control module), which in turn means you are not able to fix or prevent the A8 shudder. That can be done at any other point in time, though, for 4 extra credits (and +1 for the FSCM if you ever want to tune the exhaust as well).

Originally Posted by bereic

With this you are confusing me now.. :-).
I do not want to touch the tune on VMAX and TQ.. only the AFM and 3rd Gear.

That's fine. The way this works with HP Tuners is that a single tune file can contain calibration data (a "tune") from 1..N controllers ("modules"). As an example, my tuner sent me a file that contains data for the 3 controllers he tuned, the ECM, the TCM and the FSCM, all in one file (I highlighted them using different colors).

It is eminently possible to just read the calibration of only 1 supported controller from the vehicle (say, the ECM), change it and write it back, leaving everything else unaltered. If you save such a tune, you will only see 1 controller in there as opposed to my tune that has 3.

Hope this makes more sense now, apologies for inadvertently confusing you.

[arpad_m]

Also, you can experiment with HP Tuners' software, it's free to download and use to read the car or load/examine/compare tune files, the only time you need to pay is when you buy their hardware and then again when you want to write a modified tune back (from then on, you can write your vehicle again any number of times with no additional payment).

You can see and examine a bunch of 6th gen Camaro tunes other people uploaded to the site using their tune repository that you can access at https://www.hptuners.com/my-account/tunerepository after registration.