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Old Jun 8, 2007 | 02:00 AM
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Didn't find this info in the faq or searching. I have an 04 z06 thats under warranty and I'd like to keep it that way. Only powertrain mods are intake and tune. Couple of basic questions....

If I re-flash to a stock tune/program, am I correct in saying there isn't any evidence of previous tunes?

I assume there must be some internal logging in the ECU, max revs, error codes and such. The tune I bought the car with has a rev limited raised to 7k. Will resetting the battery clear this memory? If not, I'm guessing there must be a simpler alternative to reflashing the pcm entirely?

Thanks,
Mike
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Old Jun 8, 2007 | 11:57 PM
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returning to stock tune there should be no trace of ever being modified. I've worked at a GM dealership, and the Tech II they use I don't think would even pickup up on one that has been tuned.

Are you having a specific problem that needs warranty service that you are worried about?
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Old Jun 9, 2007 | 12:40 AM
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Originally Posted by idlingmike
Didn't find this info in the faq or searching. I have an 04 z06 thats under warranty and I'd like to keep it that way. Only powertrain mods are intake and tune. Couple of basic questions....

If I re-flash to a stock tune/program, am I correct in saying there isn't any evidence of previous tunes?

I assume there must be some internal logging in the ECU, max revs, error codes and such. The tune I bought the car with has a rev limited raised to 7k. Will resetting the battery clear this memory? If not, I'm guessing there must be a simpler alternative to reflashing the pcm entirely?

Thanks,
Mike
As stated, there should be no trace of other tunes.

The PCM stores error codes... but not in permanent memory (AFAIK the only time permanent memory is used is in the case of an accident where the air bags deploy... it then records items such as brake , gas, seat belt, etc... to permanent memory for liability purposes)

Per the FAQ sticky, losing power (resetting battery) will not cause the flash memory to revert to stock... it will only clear temporary tables like idle learn, fuel trims, etc...

The PCM uses flash memory... only way to change the code is to reflash data to it
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Old Jun 10, 2007 | 03:34 AM
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Thanks for the info!

busta9876: No problems, this is a new world to me (only fast cars I've owned are a few turbocharged imports) and just wanted to get some info.

-Mike
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Old Jun 10, 2007 | 07:08 AM
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Originally Posted by idlingmike
Thanks for the info!

busta9876: No problems, this is a new world to me (only fast cars I've owned are a few turbocharged imports) and just wanted to get some info.

-Mike

I would also recommend lowering that rev limiter back down t0 6600, LS6 springs are a little more heavy duty, but not meant to turn those kinds of rpms with any consistency
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