Topic: ECM swap

[TC-GXP]

Hopefully this is the right place for this question.
I was going to buy a spare ECM and TCM to get some tuning done to them and keep my warranty intact as best as possible but had a few questions.

If the stock ECM or TCM are removed for an amount of time and I put them back in for a warranty repair will it be obvious to the dealership that these computers have been out of use? What I mean is would there be any date codes evident in the computer that say "hey I've been unplugged and on the shelf  for 6 months"?

The odometer mileage isn't logged through the ECM is it? I didn't think it was but I can't think of where that is stored unless it's in the unit itself. Any words of wisdom from anyone who's done this?

[Arabas]

the odometer mileage is stored on the BCM and NOT on the ecm, so no prob with this.
afaik, there is no such "clock-calendar" on the ecm and one can not see that.
what i know for sure is that dealers (and GM hq) can not read if and when the ecm has been tuned or not (taking for granted that you have the stock tune loaded when they inspect the car) - applies to some of the tunes out there.
what i also know is that plugging and unplugging ecm's can potentially damage the pins...

so, having a spare ecm just in case is good, but removing it could be dangerous. i suggest to just load and unload your tune whenever you want, using the right hw and sw (depending on your tune)

[TC-GXP]

Thanks!

[Sol Asylum]

To add to what Arabas said, the Trifecta tune is supposed to be undetectable.  However other tunes are detectable so flashing a tune and then reflashing it back to stock if you need to take the car back for work would be detectable.

As for ECM damage from R&R can happen if you are not careful when plugging/unplugging the connectors.

Many others have done what you are wanting to do and that works just fine.  There are some differences between ECMs over the model years, 07's are are not interchangeable with 08-09 but 08's and 09's if I remember correctly are interchangeable with each other.  Others can correct me If I am wrong on that one.

[TC-GXP]

Thank you too! I saw a ECM and TCM on ebay pretty cheap so I was thinking I'd go ahead and do it. The prices are cheap enough that it makes me skeptical of the quality but the vendor has good feed back so I might take the plunge and hope they're new Delco units as advertised. 

[DickW]

I have owned an exrta ECM for 3 years. I have swapped out twice to take the car to the dealer with no problems. You just have to be careful.