Say you want to tune an SS/TC but you want to keep warranty, So you swap out to another ECU, Will the dealer be able to tell that you swapped out the ECU if you swap back to the stock one for warranty work?

Reason I ask is because some people say the dealership cant tell but others say the dealer can tell when the original ECU was taken out and replaced.

 

well if you put the stock one back in and its untuned you should be alright...but if you go in with your tuned ecu then they will know

 

From what I've seen, they cannot tell but they can tell if you get a tune and then revert back to a stock tune. You might be mistaking reverting to a stock tune with changing to a stock ecu. Dealer can tell if you have been tuned, but were retuned back to stock. But from what I've read, they cannot tell if you swapped the actual ECU.

 

/thread. use the search tool. this has been covered already and yes they can tell.

 

Yep, a tech said in an old thread that the ECU stores the mileage when it's pulled/put back in and will show the gap in between.

 

So, there is no point in buying a second ecu to swap before taking it in on warranty work?

 

exactly.

uploading stock tune> ecu

oh and techs can not tell if you revert back to stock tune.

i can promise you this, spoken right from a techs mouth

 

So tune it, and keep the stock tune, check. That lessens the price of getting a tune for me. I paid for the extended warranty and I sure plan to use it LOL.

 

I've often wondered why no one takes OnStar into account when they talk about swapping ECU's or reflashing back and forth before going to a dealer. I would thinkt hat once you set a CEL that information is captured automatically by OnStar and will appear on your monthly OnStar diagnostic report. Then you swap back in the the original ecu or reflash and take it to the dealer for service. Shouldn't there be a history of CEL for them to see? Anyone work a dealer that can shed some light on what type of diagnostic information they get from Onstar?

 

What does proving you had a CEL mean to a dealer? people own scan tools that can erase codes

 

You erase the CEL but you do not erase the history. The dealer can use the TECH II to scan the history of codes that were set by the car. If you are swapping the ecu won't you loose that history? I would think the dealership would think that something was funny with the car.

Maybe our version on OnStar isn't sophisticated as other GM models but on my parents STS, OnStar reached out to them when their CEL light came on. They ran a diagnostic check right there on the side of the road and even set up the appointment with dealership and advised them of what was wrong with the car. That way parts could be ordered in advance of the car getting htere to reduce down time.

 

IIRC the mileage is stored in the BCM not the ECM.

 

I'm going to test this out at my local dealer who lets me use all their stuff. I'll flash back to the stock file superchips copied and see if the CVN numbers of the calibration still line up. What i was told was that if a calibration is flashed to the car with anything other than a tech2 or GMmdi that the CVN numbers will be off. I was also told that the ECM keeps track of how many times it's been flashed .

 

i was told tec2 can not tell. it only can read whats on it

maybe canadas different from the states

 

Either that or simply disconnected your battery for safety while working on something on the car/ replacing the battery/ checking the battery/ having a dead battery. No electrical charge = taking out ECU.

I thought histories were retrievable/deletable too.. somebody correct me on this.

I'm with you on this one. There's no reason for it to be on the ECM. That would also mean that people would be yankin' other people's/junkyard ECMs so they could sell a car as "low mileage" or something since it's so easy to do. No real security against odometer fraud if it's in an ECM that takes only a minute to take out.

 

When you log in with a proper scan tool, you can erase all the codes both current and stored in history to start with a clean slate.

 

Tune it and have your tuner keep the stock tune.


GET TUNED ON A DYNO BY A PRO NOT BY JOE BLOW WITH HP TUNERS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


I hate to come on here and burst all ya'lls bubbles.

I have owned an SS/SC as well as HPtuners.

I have seen an SS/SC with a Psykosteve tune running a 2.8 and other bolt ons go pop.

I watched my Buddy's SS/SC tuned by Black Cobalt Paul go pop.

And I watched another guys HP tuners street tuned cobalt go pop.

A canned tune is crap.

Get it tuned by someone who knows WTF they are doing.

TRUST ME.

If canned tunes were so good then why do all the GTO/Camaro owners get dyno tunes after they put a lot of mods on? Have you ever seen a 500WHP GTO tuned with a handheld by the owner? If its tuned with a handheld its tuned by a pro on a dyno.

There are more things to worry about in a Cobalt Turbo/Sc than AFR's. Most people overlook IAT's Knock IDC etc etc.

 

I think your preaching to the choir here man, most people know to stay away from a canned tune

 

If that was true Trifecta wouldnt still be in business and HPtuners wouldnt have such a large market base on this website.

Buying HP tuners IMO is a HUGE waste.

You can get a legit dyno tune for half the price make twice the power and retunes at any reputable shop are under 125$.

 

100% false. There is NOTHING at the dealer level that can tell if an LNF ECM has been swapped.

 

i have 2 ECU's and swap them frequently. milage isnt effected. only oil life i believe...

 

There are plenty of "professional" tuners with a dyno who dont know a fraction of what some joe blow tuners know. In the end it all comes down to doing research and knowing a little more about the person tuning your car than what he charges for a tune.

 

ok so say i just want a little more umph out of my ss/tc.... would you spend 400 bucks on a superchips and be able to smoke most v8s on the road and have the option to take it back to stock, or buy a second ecu for 200 bucks and then another 125 for a dyno tune(i feel 125 is low, most shops around me charge 100 up front and 50 for each run ofter + the tune if they can even tune the ecm in our cars) and have to repay for it to go back to stock so you can take it to get warrenty work.....i guess its all what you wanna do with it. personally i would rather get 40 hp and 50lb ft. and be done with it......

 

hit it right on the head.

no dyno tunner around my city knows sweet **** all about tuning LNF's. so no thanks ill pass

id rather data log and let Vince and Trifecta..somone who tunes as HIS JOB to tune my vehicle.

 

Okay so i'm a little confused then. Are we on the consensus that a Tech CANNOT tell if you have a sepearte ECM. I talked with GTPprix today(who works at a dealer) and he said the equipment they use cannot tell if it has been swaped, also that the miles are stored in the bcm. So would I be okay with a seperate ECM?