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Uh-Oh....Looky here!

13K views 21 replies 15 participants last post by  Aerostud1026 
#1 ·
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info on GM'S crackdown on aftermarket tunes...

the following is the p.i for calibration confirmation from GM

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#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




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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 jay.dankovich@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: jay.dankovich@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.
 
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#5 ·
Let's address some essential issues:

1) Understanding Tunes and GM Validation.

Before anyone can understand what the tune does one needs to understand how GM validates a part.

GM tests their product so there is margin for error. For most folks they never get that close to the limit. GM builds their product so if there is a failure it should be discovered during the warranty period and it will be covered if a repair is necessary. A tune, 'safe or whatever else you want to call it' changes all of that, It puts stresses on components that GM does not test for. Some tuners will tell you the their tune is safe and will not cause any harm. This may be true for 95% of their customers, but...the problem occurs when your car that has the tune which is one of the 5% that fall out side the normal limits. The component may operate perfectly for years at normal levels but when additional RPM is added, or a richer mixture is added, or the spark changes, all of that can put pressure on a piston, a rod or a set of bearings that was never intended. When that pressure is exerted, the component may fail immediately or it may develop a slight crack and will continue to grow until it fails perhaps at 30 miles per hour when driving your kids to school.

We have had a few posts claiming just this....I'm not suggesting any of these cases here where due to this, I plain and simply do not know. Just a heads-up of how it could happen at what would seem to be ridiculous conditions.

2) When will a failure occur?

There is no way you can tell if and when a failure will occur. GM builds in a safety margin so that does not normally occur. When a tune is installed that margin is lost and stress starts to build in the component until something breaks. Expand that thought to the rest of the powertrain,

For instance, GM knows that the half shaft will perform fine at 505 horse power, there is a margin of safety build into it. Now, add 20 more HP to the half shafts and the safety margin is gone. Add a set of drag radials that provides much better grip. Now you have more HP and a tire that does not slip when it should. What do you think is going to break? Probably the half shaft. EXCEPT if the half shaft is a stronger product that the average, say it is a really good one.

Now that additional HP and the higher slip resistance from the changed tires and the additional stress is transferred to something else. Add to that a driver that lets the wheels hop until they catch traction and the differential case is now split in half. This shouldn't be a mystery. All the HP and the force has to go somewhere. If the tires can’t spin because of the increased traction the ring gear and pinion gear start to push away from each other, the case that holds them together is only been tested for stock HP and stock tires. The force between the ring and pinions gears can actually break a differential case in half. Same thing with the transmissions.

The input and output shafts are rated for so much HP and so much tire slip. Alter the safety margin and shafts get twisted off. Not because they are defective but because higher stress loads are being applied than the part was designed to take. It is a very balanced package to a specific HP and a specific amount of tire slip. Changing either one beyond the test limits and things start to break.

3) Why not build the car stronger?

Some ask they why doesn’t GM build them to withstand 600 HP to be safe? The answer is you can’t and keep the car affordable. GM can build the components to withstand 650 HP but they would have to charge the same price as a ZR1. It ends up pushing the car out of the price level that most drivers are willing to spend.

4) Why not just swap the ECM/PCM?

Can the ECM/PCM be changed and no one will know? No! Each module has information stored in it. Some is transferred when it is reprogrammed and some starts all over again when a module is changed. Kind of like keeping score. The module knows the miles how long it has traveled since a emission test was completed and many more little bits and bites. When a new module is put in some of the data gets moved and some does not. When a suspected tune is discovered and a technician starts to look for clues, there are more than enough clues which will not be revealed here to confirm that this is not the PCM that has been running in the car.

5) How is the used car market segment to be addressed?

What about used cars? As soon as the bulletin is published it is public information. I will be glad to post the bulletin number and you can ask your dealership for a copy of it. If I was going to purchase a used Corvette or a Diesel Truck I wouldn’t buy it with out checking it for a modified calibration. Using the bulletin will take less than 5 minutes to determine. If it has a non-GM calibration just be aware that it may have already been discovered by GM and there may be a warranty block on it that the owner or used car dealership may not be aware of. It is worth having a Chevrolet dealership take a look at it just to make sure.

6) Will this be able to be used on C5 cars too?

Yes!


7) Will the Service Manager at my dealership be able to get around this?

It's not so simple. If a major failure has occurred and the dealership is required to attach both print outs of the calibration numbers which include the VIN to the repair order, there may not be much room for the dealership. If they do the repair and they are audited, the dealership will loose the cost of the parts and the labor. It is actually charged back to the dealership. Also remember many of the engines are now being returned for analysis. If during the inspection the engine plant detects evidence of a tune they will call the dealership for the records. If the dealership can not supply it then the warranty claim can be charged back to the dealership.

8) If the calibration is overwritten for example 10 times, will a dealership still be able top tell a calibration has been added?

Yes.

If you think someone will not question 5 of the same calibrations entered of a period then you don’t understand how serious GM is about this.

Why is GM doing this now?

As many have pointed out repeatedly, some of the information has been available for some time. But it has been tied to the calibration part number. The part number is good information but it is not fool proof. The second part of the equations, the hidden files, have just been established and validated 100%. GM wanted to make sure it was valid and the information was dependable before they took it to the dealerships.

9) Legal Issues:

Is this legal?

Can GM block my warranty?

Yes.

It has been run through the legal beagles and it is legal. In the warranty booklet there are 4 separate notations that modifying the vehicle from the original production will void the warranty and repairs will not be covered.

There were some comments on taking this to court.

Who is going to spend the dollars to try a case when the repair is going to be in the $15,000 area. I image GM has enough lawyers sitting around that they can tie this up for some time all the while the car is not running. The bottom line is when a calibration is changed the car is altered and GM has stated it does not warrant repairs once the vehicle has been altered. I'm not sure why this is such a hard concept to grasp.

10)What about Magnuson Moss?

You're kidding right?


11) Where does the information come from?

Many of you know I have attended many of the NCM HPDEs that include many of the GM engineers. I have built an honest relationship with many of them. I was one of the first lucky one's out on the track with my Z06 on a regular basis. I continually provided real customer information to them and they provide honest feedback to me. It’s a relationship built on trust. This information is coming straight from GM. They trust me not to ask questions I realize they can not and will not answer, and they trust me not to provide their names and positions which would result in bombardment of Internet questions. Those of you who have met me have seen this first hand. Please do not get hung up on which individuals and departments it came from. There are enough forum members here who can verify my integrity and my contacts. Let's keep this about our beloved Corvettes!
 
#6 ·
Ok so what happens if you get your PCM reprogrammed and say something in your transmission breaks. What if you had it flashed back to original? That would essentially keep all of the other little things that doesnt get transferred when you install a new PCM and it should keep all the numbers in order right?
 
#14 ·
FYI That process/software ect is about 10-13 years old. GM has been doing it forever and periodically sends out updates like this to remind people. It's just a TSB, how many of you have had dealers who didnt even know there was a TSB out for a specific issue? Exactly ;) Worst case buy a new ECM/PCM/TCM and stop worrying :)
 
#20 ·
Hey guys, I just wanted to make you all aware of what GM has the ability to do. I guess they are buying more rearends and trannys than they expected to. I don't have hard numbers, but I'm guessing the "mild" tunes are not causing that much damage to these trucks, but the few radical tunes (and you know who you are) are making everyone susceptable to this process. I think we all know that, even stock, the trannys and rearends have been known to fail without much provocation. As many have stated, GM set the parameters for what they believe these vehicles can handle, why should they be expected to pay the bill for someone second guessing their engineers. If you want to play, be prepared to pay. It doesn't sound like there is a fool proof way to beat GM when it comes to whether or not they can read the hidden files in the ECM/PCM. Obviously some have not been caught, but others have (or will). Just something to think about if you're still in warranty. And you guys with the 07's and 08's have a hundred thousand miles to gamble with!
 
#21 ·
And you guys with the 07's and 08's have a hundred thousand miles to gamble with!
Yeppers... That's what I'm saying...

I'm also saying that, even though they all say "for off road use only", it had previously been said that the dealership can't tell if you have a tune or not, so you may as well get a tune, because it won't effect your warranty if they don't know about it... but now they can...

Mike
 
#22 ·
Well I guess it's good I've waited......I wanted to wait till I was done modding the things that have to do with the tune.....

I have a CAI, Exhaust I will be getting exhaust done beginning of may...and I'm probably going to need new tires by mid summer.....and I only have 6k left on my warranty.....so by the time I get my tune (After Exhaust and Tires) im sure im going to be out of warranty anyways...

Hopefully PCMFORLESS will be doing the 99 dollar tune special sometime again, if not..no biggie....from what everybody says about them the full price tag will be the best money i've ever spent
 
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