So I was at my local Chevy dealer talking to them about extended warranties. I knew a dyno tune will/should void your warranty. When I talked to the service department if they could check the computer to make sure it was never tampered with, that the car never had a dyno tune done, they said there is no way for them to know. I responded with that I found that very hard to believe. The service guy then talked to 2 senior techs and they agreed. They said that they could reflash the computer for a cost of $100. But reflashing it wouldn't tell them if the car ever had a dyno tune done? They agreed.

With that being said, if someone wanted to dyno tune their car, and then they had a failure with the motor (I find it hard to believe that a simple tune would cause failure to the motor, BTW), how would the failure not be covered under warranty if according to the dealer, they have no way of knowing if a tune was ever done?

 

There is a TSB out that tells the techs exactly how to read the computer to see if it has been tuned. Do a search, tune and take the chance on loosing the warranty, your choice.

 

I want to hear about this also . I've read that the dealer can trace a programmer or tune.

 

Original "heads up" and follow-up discussion:

http://forums.corvetteforum.com/1564742766-post1.html

http://forums.corvetteforum.com/c6-c...t-from-gm.html


Case study:

http://forums.corvetteforum.com/othe...ed-w-tune.html

 

I believe the TSB instructs the tech take a photo of the Tech2 readout and email it to GM for their analysis. I take it GM doesn't want to let out to the techs, or the general public, how they determine, from looking at the readout, that a tune has been done.

It puts a potential buyer of a pre-owned Vette in a terrible position. I would not purchase a used vette, especially a Z06 or any Vette that has had any type of performance MOD, such as a CAI. If the previous owner was looking for additional HP by installing MOD's, then it's reasonable to conclude that he might have had a tune done.

GM should have a program in place so the dealer's tech can do the scan and send it to GM for analysis. Charge a fee for the analysis to the dealer and let the dealer include that fee in the cost of selling the car. For someone that is not buying a Vette from a Chevy dealer, the dealer should charge a fee to the customer. It's not up to a Chevy dealer to perform free services for an individual selling his Vette, or to Harry's Used Car lot down the street.

There would still be the same disclosure on the warranty about a tune voiding the warranty.

 

I worked with a 2009 C6 this morning. The C6 which had been previously been tuned had a problem with the fans not activating which was causing the car to overheat. He brought it to the dealership and they installed a new fan and a new PCM computer system.

It was no secret that this car had a cam and was tuned. It had a 231/237 cam on a 111 LSA with a GMPP exhaust.

The dealer didnt have an problem fixing the fans, replacing the computer and uploading a stock 2009 tune.

The owner drove to my house and I uploaded his dyno enhanced tune and he was a happy camper again.

 

I have no idea if the Tech-2 will read enough table information to know if a tune has been done. I am 100% positive that somewhere in Detroit they can determine if the PCM is currently modified.

I am more interested in how things would work if they can't/won't check the PCM before they sell a warranty how would they void the warranty later? This is more interesting in the case of a used car where the buyer doesn't know that the PCM is modified.

Myself, I knew the car was modified and that my powertrain warranty is pretty well done for, but I bought it knowing that. Guess we now need a CarFax as well as an HPTuner for used car shopping

 

Would the dealer be so helpful if the owner(with the cam & tune) had taken his car in with a rod sticking through the side of the block. GM will not let the dealer install a new engine and then GM pay for it under warranty, without the dealer running a scan and emailing it to them(GM) for analysis. GM doesn't require the dealer to run a scan on the engine, etc,and submit it, if a window fails to go up and down or the A/C is acting up.

Lets say a Vette owner installs a CAI, long tubes and a Fast manifold and then has it tuned to maximize the HP based on the MOD's he has done. He later decides to sell the car, and wants to get as much money as possible and sell it as quick as he can, so he removes the CAI, the manifold and the longtubes. He then sells them separately on the Internet. Not wanting to spend the money to have the tune removed, he leaves it in. Someone buys the car thinking it is completely stock(remember the owner has removed all visible signs of modifications and "forgets" to tell the new owner about them) and now the "tune" does not fit the car. The new owner has a major engine problem later on that could have been caused by the 'tune" not being correct for a stock engine, and GM refuses to replace the engine under warranty.

I'm not saying everyone is out to screw a potential buyer, but it has been done. Also, if the previous owner traded the car in on a new Vette, the dealer sees the car is "stock" and then sells it to a unsuspecting new owner, who gets hung out to dry; the previous owner, the "tuner" or the new owner?.

 

Great links in this thread. All good info to know. Definitely not getting a tune now. I will throw it up on the dyno later this year to see what kind of numbers she puts out. If it looks "normal" then I won't have anything to worry about, but if it's pulling some 20whp more than it should, then I'll know something is up.

 

does your car insurance cover you if you crash at the drag strip? No, but guys still go.

Will a doctor replace your kidney for free if the previously replaced kidney failed? No

Will GM replace your motor if you have a big fat cam in there, and you throw a rod through the side? I doubt it.

If you have good repore with your dealership, they may give you some wiggle room, but its a business. Business dont want to lose money
( unless the government is going to bail you out every year )

GM gambles that your car will last 5 years or 100,000 miles. If you keep blowing your motor or transmission, GM will do a little math to figure it out.

But its the 1%ers on here that always need more power and get their cars tuned, add heads and cam, add an FI system, the car still last for a long time.

 

GM counts on the fear of loosing a warranty by making mods, which allows them to offer long and extended warranties.

If a poll was taken to determine the percentage of major engine failures to cars that were stock vs. those that had mild mods (bolt-ons/tunes), I'd suspect the difference to be very slight and the rate of incidence extremely low.

But once you start going with internal mods or FI/NOS, it becomes a different story.

 

GM probably won't warranty a catastrophic engine failure after a tune.
But let me ask this question..... how many have had a tune then had a catastrophic engine failure?
I'm not saying it doesn't happen but I think it's pretty rare.

 

I just had my car into the dealer. They warrantied my whole cooling system.

Car 09 ls3 m6 full bolt ons, dyno tune, cam

they didnt flench

 

JoeC5 has hit most of the salient points along with Rick's find of relevant threads.

 

It depends on the dealer. Some dealers will not touch your car for the slightest mods while others are more reasonable by analizing if the mod effected exactly what is wrong with the car. My dealer is great. He knows that a tune will not effect an alternator going bad, etc.

 

As much as I'd love to put my Z on the dyno for a tune, I don't want to risk the chance of the motor eventually going south, no matter how remote that chance is. A bill for $15K for a new LS7 would really **** my wife off. Again, I realize the chance of that happening is remote.
On the plus side, an extended warranty at the time of sale of the car definitely seems to be a HUGE plus. Cars with warranties (that are not modded to the point of potentially voiding the warranty) definitely attract a wider audience. This is not my primary reason for an extended warranty, it's just a plus. I don't plan on selling my car anytime soon.

What I am concluding from my original post is that there is a way for GM to find out if the computer has ever been tampered with, and this is not up to the dealer. Something the dealer didn't tell me, or something they may not have known...at least the 3 guys I talked to not including the 2 techs they spoke with.

 

There is a way. And it's something GM will request a dealer do in the case of a large warranty claim. They likely won't do it for a small claim. But for something such as a new engine or trans, you better believe they're gonna check.
As for mods, you can do whatever you want and it will not void your warranty....EXCEPT change/alter the programming on any of the factory control modules.

But as has been said, depends on the dealer and your relationship with them.

Case in point...I've got a little warranty left that is still active on my fairly heavily modded '08.
My A6 just let go last week...Now, I could be a d**khole and try to get a new trans under warranty.
But I know it's my issue...my car is tuned, cammed, ported, blown, etc, etc.... And because I was up front with them about it and am paying for it myself, my service mgr offered me a brand new stock A6 at what I know is a pretty deep discount...on top of keeping my warranty active in case any little stuff goes wrong.
I'm honest with them and they treat me very fairly, and they know I will continue to come back because of it.

Again, it ENTIRELY depends on the dealer and your relationship with them.

 

Very well said.

 

When you start tinkering with what the factory shipped out...if you're lucky the minor problems will not be an issue. If anything major happens you're out of luck as it should be.

 

Ya'll be careful now you're going to upset the chosen few that think we should all pay for their exploits...