Flashing Computer to Stock Specs [Archive]

talon90

01-23-2009, 09:17 AM

Not sure I agree here.

We leave no such trace in the PCM after flashing a tune, same for once it is returned to stock...nobody would ever be able to tell you had flashed a non-stock tune from the Predator.

I certainly will defer to your expertise as this is what you do for a living but it contradicts information that I have received from other sources.

When a file is changed it is effectively time and date stamped as to when the change took effect. If that time and date information is different than what the TIS system indicates it can cause a reason for further investigation. What would cause that to happen is any variation in the CVN (calibration verification number) which is that check digit that I referred to in my previous post. Here is GM's protocol for aftermarket tunes. Please note that it does not state to validate the values, it simply states to validate the calibration part# and compare it exactly to the calibration verification number. Are you saying that your tune leaves the CVN in tact?

#PIP4386: Identifying Aftermarket Engine Calibrations - 2.0 2.2 2.4 2.8 2.9 3.0 3.1 3.2 3.4 3.5 3.6 3.8 3.9 4.2 4.3 4.4 4.6 4.8 5.0 5.3 5.7 6.0 6.2 7.0 7.4 8.1 - (Apr 8, 2008)

Subject: Identifying Aftermarket Engine Calibrations

Models: 2005-2009 GM Passenger Cars and Light Duty Trucks

except Pontiac Vibe, Chevy Aveo, and All Saab Models

--------------------------------------------------------------------------------

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
A dealer may have the need to verify engine calibrations. If a dealer feels an aftermarket power-up calibration has induced engine and/or drive train damage, there is now a way to verify what calibration is currently in the vehicle.

If a suspicious hard part failure is observed in the engine, transmission, transfer case, or driveline, perform the calibration verification described to determine if a non GM issued engine calibration is installed. Non GM issued engine calibrations subject driveline components to stresses different than those that these components were validated to. Repairs to transmission, transfer case and / or other driveline components where a non GM engine calibration has been verified, are not covered under the terms of the New Vehicle Warranty.

Recommendation/Instructions:
Instructions for confirming Calibration Verification Number (CVN)
• Go to TIS2WEB

• Select Calibration Information (SPS Info)

• Enter VIN

• Select "Get Cal ID"

• Select ECM Engine Control Module

• Hit "next"

• Select "Complete History"

• Print

Take Printout to Vehicle along with Tech II
• Plug in Tech II

• Go to diagnostics and build the vehicle

• Select Powertrain

• Select the engine

• Select F0 - Engine Control Module

• Select F4/F5 - I/M information System / Module ID information*

• Select F1

• Compare the calibration ID and Calibration Verification Numbers (CVN) to the Calibration Verification Numbers (CVN) on the printout.

* This step may vary by controller; use the Module ID Information in the Engine Controls.

Although the part numbers will be the same for each, it's the CVN that will determine if the calibration is GM issued.

If ALL of the CVN's are EXACTLY the same, the calibration is GM issued.

If the part numbers match and ANY calibration verification numbers (CVN's) do not match the printout, it is likely that a non GM certified calibration has been installed.

In order to document the case - a CLEAR digital picture should be taken of the TECH 2 screen showing the VIN and the CVN's that do not match the TIS2WEB printout. The picture and a PDF copy of the TIS2WEB printout should be forwarded to ***email edited***@GM.com for verification along with the VIN and the reason the vehicle is currently in for service. Please copy your GM Area Service Manager (DVM/DSM) on the e-mail. GM will verify if the CVN's are not GM issued and respond via e-mail within 48 hours.

If both the Part numbers and the CVN are different, photograph the part numbers and CVN's on the tech 2 screen as described above, assuring the VIN shows clearly in the photograph of the TECH2 screen, and check to see if the vehicle has the latest released calibration. If the latest released calibration is not installed in the vehicle, the part numbers will not match , and the CVN's won't either. E- mail the original Part Numbers and CVN's found in the vehicle on the TECH 2 to: ***email edited out ***@GM.com to check if the calibration and CVN matches a previous release. Recalibrate with the latest released cal and re-check against the part numbers and CVN's that are released.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.


SmokinVette.com Forums > Corvette Forums > C6 Corvette Forums > C6 Scan & Tune > Flashing Computer to Stock Specs PDA : Flashing Computer to Stock Specs Yankee Doodle 01-23-2009, 07:30 AM Am I understanding this correctly. If you have a tune flashed onto your cars computer, can this later be flashed back to the OEM stock specs where the dealer can't see that the computer has been tampered with a aftermarket tune? I was told the file remains "hidden" on the ECU and can't be deleted nor detected? talon90 01-23-2009, 08:22 AM If they look deep enough they can find traces of the aftermarket tune. The reflash will not completely overwrite the check digits that are available in the software. They will need to work to find it but if they have cause to do so, they will. The only way to completely mask a stock tune is to have a spare computer that has not been flashed. If you have an aftermarket tune you also will need to verify that the tuner has not locked the tune which will prevent overwriting it with changes to go back to stock without their involvement. Mike@Diablosport 01-23-2009, 08:59 AM Not sure I agree here. We leave no such trace in the PCM after flashing a tune, same for once it is returned to stock...nobody would ever be able to tell you had flashed a non-stock tune from the Predator. talon90 01-23-2009, 09:17 AM Not sure I agree here. We leave no such trace in the PCM after flashing a tune, same for once it is returned to stock...nobody would ever be able to tell you had flashed a non-stock tune from the Predator. I certainly will defer to your expertise as this is what you do for a living but it contradicts information that I have received from other sources. When a file is changed it is effectively time and date stamped as to when the change took effect. If that time and date information is different than what the TIS system indicates it can cause a reason for further investigation. What would cause that to happen is any variation in the CVN (calibration verification number) which is that check digit that I referred to in my previous post. Here is GM's protocol for aftermarket tunes. Please note that it does not state to validate the values, it simply states to validate the calibration part# and compare it exactly to the calibration verification number. Are you saying that your tune leaves the CVN in tact? #PIP4386: Identifying Aftermarket Engine Calibrations - 2.0 2.2 2.4 2.8 2.9 3.0 3.1 3.2 3.4 3.5 3.6 3.8 3.9 4.2 4.3 4.4 4.6 4.8 5.0 5.3 5.7 6.0 6.2 7.0 7.4 8.1 - (Apr 8, 2008) Subject: Identifying Aftermarket Engine Calibrations Models: 2005-2009 GM Passenger Cars and Light Duty Trucks except Pontiac Vibe, Chevy Aveo, and All Saab Models -------------------------------------------------------------------------------- The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI. Condition/Concern: A dealer may have the need to verify engine calibrations. If a dealer feels an aftermarket power-up calibration has induced engine and/or drive train damage, there is now a way to verify what calibration is currently in the vehicle. If a suspicious hard part failure is observed in the engine, transmission, transfer case, or driveline, perform the calibration verification described to determine if a non GM issued engine calibration is installed. Non GM issued engine calibrations subject driveline components to stresses different than those that these components were validated to. Repairs to transmission, transfer case and / or other driveline components where a non GM engine calibration has been verified, are not covered under the terms of the New Vehicle Warranty. Recommendation/Instructions: Instructions for confirming Calibration Verification Number (CVN) • Go to TIS2WEB • Select Calibration Information (SPS Info) • Enter VIN • Select "Get Cal ID" • Select ECM Engine Control Module • Hit "next" • Select "Complete History" • Print Take Printout to Vehicle along with Tech II • Plug in Tech II • Go to diagnostics and build the vehicle • Select Powertrain • Select the engine • Select F0 - Engine Control Module • Select F4/F5 - I/M information System / Module ID information* • Select F1 • Compare the calibration ID and Calibration Verification Numbers (CVN) to the Calibration Verification Numbers (CVN) on the printout. * This step may vary by controller; use the Module ID Information in the Engine Controls. Although the part numbers will be the same for each, it's the CVN that will determine if the calibration is GM issued. If ALL of the CVN's are EXACTLY the same, the calibration is GM issued. If the part numbers match and ANY calibration verification numbers (CVN's) do not match the printout, it is likely that a non GM certified calibration has been installed. In order to document the case - a CLEAR digital picture should be taken of the TECH 2 screen showing the VIN and the CVN's that do not match the TIS2WEB printout. The picture and a PDF copy of the TIS2WEB printout should be forwarded to *email edited@GM.com for verification along with the VIN and the reason the vehicle is currently in for service. Please copy your GM Area Service Manager (DVM/DSM) on the e-mail. GM will verify if the CVN's are not GM issued and respond via e-mail within 48 hours. If both the Part numbers and the CVN are different, photograph the part numbers and CVN's on the tech 2 screen as described above, assuring the VIN shows clearly in the photograph of the TECH2 screen, and check to see if the vehicle has the latest released calibration. If the latest released calibration is not installed in the vehicle, the part numbers will not match , and the CVN's won't either. E- mail the original Part Numbers and CVN's found in the vehicle on the TECH 2 to: email edited out *@GM.com to check if the calibration and CVN matches a previous release. Recalibrate with the latest released cal and re-check against the part numbers and CVN's that are released. Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. DynamicTuningSolutions 03-18-2009, 09:38 AM If they look deep enough they can find traces of the aftermarket tune. The reflash will not completely overwrite the check digits that are available in the software. They will need to work to find it but if they have cause to do so, they will. The only way to completely mask a stock tune is to have a spare computer that has not been flashed. Actually VIS will confirm whether or not the stock PCM/ECM/TCM is installed in the vehicle as the replacement ECM/PCM/TCM will have a different serial number than that indicated by VIS. Then again, if you simply purchase a stock PCM/ECM/TCM to use for tuning it will be completely and totally masked if you then put the stock one back in there. However you will have to do a VATS relearn when swapping ECM/PCM.